As a professional tech, I think you should cover a planetary gear set with a whole video of its own. Sun gear is its gear count, ring gear is its gear count, planetary carrier is the the effective gear count of the sun plus the ring. This arrangement based on one member input, one member held and the other output can yield underdrive, overdrive, forward, reverse. You should do a whiteboard video to describe the various applications of a planetary gearset itself on the automotive industry. I think so many laypersons do not understand the basic concept of planetary gears. The Toyota Synergy drive is probably the most genius/simple transmission ever designed. As a heavy truck tech, we have planetary wheel ends and 2 speed rear axles using planetary gearsets. I think the general public would greatly benefit from your explanation of how these gearsets work. Love your work! Keep it coming!!!
This please Jason! I had to watch your explanations 4 times to minimally understand the mechanics of things here. (I'm not sure I fully did though... 😅)
Was going to reply regarding the Toyota Synergy / hybrid transmission, and then you said it. Best “automatic” transmission I’ve ever owned. Stepless drive, and without a single clutch or brake pack or actuator to fail.
Even when I have no need to know the subject matter, in this case why 2 vehicles have 2 different 4wd, I like how Jason explains stuff… and painlessly stuff more knowledge into my brain.
Finally a good video combining all the knowledge into one. This is like hundreds of pages of 4Runner vs GX vs 200 vs Tacomas forums consolidated into one video.
The forums can be a great resource, but are truly a mess! I was thankful to have Toyota's engineers help with official documentation and questions such to sort it all out!
@@EngineeringExplained I also love how we have easy access to all the 4x4 chassis next to each other. Instead of having to rely on consumers to dig around and compare themselves!
Yep. Plus the torsen center differential with pretty much the same F/R ratios have been in use since 2003 in a lot of Toyota/Lexus full time 4WD vehicles.
Jason with Engineering Explained and Ryan at FortNine are two of the best teachers of both Automotive and Motorcycle Engineering on RUclips. Only difference is Ryan slides in some slick humour. Both are amazing at what they do.
@@kamilkalfaoglu If the center diff is locked, the front and rear driveshafts must always rotate at the same speed regardless of resistance at the tires. So if the back wheels are up in the air and the front is on nice rough pavement, 50/50 would mean that half of the engine's torque is being used to spin the rear wheels. They're freely spinning, so 50% of engine torque would make them spin much faster than the front since the front has resistance to overcome. But a locked center diff can't spin the rear faster than the front, so a 50/50 torque split is not possible in that scenario. The front and rear driveshafts of a locked center diff must spin at the same speed, while only the front one is resisting the rotation. Hence virtually all of the engine torque is going to the front, because the back isn't resisting rotation. (Realistically, there is friction and rotational inertia so the rear tires will still require a little bitty bit of torque just to get them turning at the same speed as the front, so it's not quite 100/0, but it's close.)
@@jamieflournoy thank you so much. I understand right now. When I saw the 0, I thought that part wasn't turning despite the lock, but actually, it is turning but almost no torque is needed.
Is it just me or are other viewers excited when the white board gets revealed in one of these videos? I am always waiting through the intro to see what Jason has in store for me on the white board. This one is a GREAT one!
What many don't realize is that the 4th gen 4runner had everything available at its disposal, but only in the V6 models. You could select 2hi, 4hi, 4lo. And since selecting the Torsen center diff was independent of whether it was in 4hi or 4lo, you could technically run in AWD Lo and never bind. It was the best of all worlds, but my guess is Toyota had to simplify it because most people didn't understand how it worked. Many still get the new systems confused which have less to choose from.
They seem to go back and forth on it. 80 series locked the center diff in 4lo but you could mod it to not and everything would be fine. Same for a period of time in the 100 series until they stopped and allowed you to do 4lo independently of locking the center diff without any mods.
@@MarkRose1337 Yep. I didn't mention the V8 in my original comment to try and keep it short. But it does everything the V6 does, except it can't go I to 2hi. I've gotten in so many arguments with V8 owners on the 4runner Facebook groups because they think just because the V6 has 2hi, it automatically means it's part time 4wd. (many V6 owners also think the same thing but don't necessarily argue as much in my experience 😂).
I boggles my mind why the non-Limited 5th Gen 4Runners did not have the center diff (like they did on 4th Gen). I’ve had 3 5th Gen Limited (since 2010). I would have liked at TRD ORP with KDSS, but since I live in New England, the AWD took priority…
I love this guy. He takes the incomprehensible and makes it almost understandable. 😁. Seriously, this is a great channel. Even in a case like this where the answer is obvious, it is fun to learn the reasons and understand why.
3rd gen 4Runners hsd a lovely multimode transfercase option. It was 4x2, push of a button gave you AWD open center differential that waa shiftable into AWD low range which was extremely handy backing trailers with surge brakes up steep driveways and thrn you could lock the center differential for a true 50/50 locked center diff in high or low range. This option was carried over into the V6 4th gen 4x4s and then disconnected for the 5th gen.
The manual shifter for the transfercase in the 5th gens are perfectly fine and less likely to go wrong. I'd choose mechanical over electronic anyday. You just have to hold them in for a few seconds with pressure to make sure it properly engages.
@@username8644 third gen 4Runners have an AWD shift actuator as well as a mechanical J shift and LC style fore and aft transfercase style. The J shift tcase you see ina 5th gen is straight out of the 3rd gen 4Runner parts bin.
In South Africa, the Landcruiser only comes with a 2.8 litre turbodiesel engine, also found in the Hilux. It's got something like 500 Nm of torque from as low as 1200 rpm. It's awesome!
@@leonardc1303 the absence of the LC 75 has less to do with emissions and more to do with crash test safety regulation and the government not having a classification/exemption for basically 'specific purpose vehicle which sacrifices safety for a certain application'. The LC 75 could absolutely be made emissions compliant (maybe more emissions equipment on the diesel, maybe swap diesel for 5.7 gas), but it absolutely cannot be made modern crash test compliant without an exemption/new class of road vehicle being created with lesser standards.
I would love to have the diesel set ups yall have over here . I just can't do the right hand drive cause I drove I r h drive jeep once and I kept stopping at people's mail boxes
Same 2.8 litre D-4D turbocharged diesel engine is used in the Toyota Fortuner as well, which produces 550 Nm of torque along with 221 bhp of power. Diesel SUVs are an emotion.
My 2004 4Runner has full time 4WD. It's nice in winter when the road is alternating between snow and bare. It handles better in most situations with the center diff unlocked and I've only used the center diff lock a few times where I needed it.
I have the same thing and totally agree. I love it for winter driving. I’m about to order a Tacoma and only the Limited model can come with this AWD/4WD setup with Low Range and Center Difflock. It’s a great system. In extreme off-road, I think the Rear Differential Lock in an Off Road Model prob works just a bit better though.
As you mentioned, the 4-runner Limited model has exactly the same full-time AWD and locking center differential as the land cruiser. I trade in every 2 years and stick with the limited edition and I am nearly always off-road in Florida (sugar sand and mud) and it never lets me down. Best production off road vehicle you can buy IMO. Jeep doesn't even stand a chance against them for reliability and features.
This is actually an amazing video; I've always wondered about how AWD/4WD is implemented and if you extrapolate from this video it really makes a lot of sense. Really appreciated the no-slip torque split explanation; I always wondered how that's implemented.
Great explanation of a complex problem. As a side note, I have been driving my 2008 4Runner (RWD SR5) for over 15.5 years and it always gets 20.1 mpg in the city (with a light foot on the gas and stock 17" tires). I live in NE Iowa and it has gotten me through the worst snow storms ever with no problem. Sometimes a simple system can be the best choice.
The Toyota full-time system with the Torsen center differential is phenomenal. I have owned a 2011 GX460 and now have a 2018 LX570 and love this setup. My favorite part is the ability to put it in 4Lo with the center diff unlocked. It make parking and maneuvering my 5500 lb trailer super easy without binding. The fact that Toyota has not expanded this system in this new generation of trucks, particularly not putting it into the Tundra, and completely removing it from the Sequoia(which had full-time since it came out in 2001 MY) is very disappointing.
Totally agree! Also you can drive like a hoon in the rain and never loose grip (much). Having a locked centre can also cause understeer on loose gravel roads. I bought my 2014 Prado specifically for the AWD after coming from a long line of turbo Subarus.
@@peejay1981 that may explain why my old ST185R Celica GT-four was a (much) more understeery pig on gravel than my 4WD Corolla wagon of ~identical age. If my memory is right... the Celica had a centre diff that locked up on acceleration, and the Corolla did not.
@@mediocreman2 Make sure you specify which Subaru you're talking about. My BRZ has a Torsen LSD standard. It's not the center as the BRZ is RWD, but it's still a Torsen.
4th gen 4Runner used this version of full-time 4wd on the V-8 models and the V6 4wd models also came equipped with a torsen center diff as well but it was a part time 4wd system.
An extra bonus of full time systems for reliability is that you don't have auto locking hubs which are known to be failure points on a lot of vehicles. On my 100 series I can just push the center diff lock button while driving and it goes on/off almost instantly like an air locker would, no doing the forward/neutral/reverse dance that I've experienced on newer Tacomas. Obviously shifting between hi/low range requires you to be stopped and in neutral but it's also a straight throw lever and super smooth.
I don't know about newer Tacomas but with my 2013 I believe the hubs are permanently locked. The 2wd vs 4wd selection happens at the front diff so no forward/reverse dance is necessary.
It was great to see your inclusion of the Car & Driver article. I've always loved the way they break down automotive tech. Which, come to think of it, is probably why I really like your videos.
This was a SUPER helpful video. I have a 2023 4Runner with the part-time 4WD system. I always wondered how the full-time 4WD Limited models did it differently. I had no idea a Torsen diff (or at least this particular one) was a planetary gearset. I had a '99 Limited 4Runner with a fancy transfer case that ran the full gamut from 2hi, 4hi part time, 4hi full-time, and 4lo, I wonder how that got it all done. We also own a 2023 Outback. After this, I went back to your seven year old video on Subaru AWD systems as a refresher. There's so many different ways to do this! I wonder if an update on the Subaru video would be worth it? Looks like they no longer offer two of the four systems shown in that video, and I wonder if they've changed functionality at all on the latest generation stuff. And finally, ALL of these systems seem so complicated compared to just independent dual-motor AWD on most EVs. I look forward to electric offroading once it arrives in more mainstream, smaller models.
The 1999 had the VF3AM transfer case which has a center differential in it. It is not a torsen differential that can change the ratio if slip is detected while in 4HI - (center diff) unlocked. It is just an open differential when run in 4HI - unlocked (J-shifter in H2-H4 with the 4WD button pushed in). Nomenclature wise, the 99-00 4Runners 4WD Limited does not have 4HI part time, it is 4HI - (center differential) locked with the J-shifter in the H4L position, which locks the front & rear just like a part time 4WD. 2001+ 4Runners and subsequent multi-mode J-shifter changed the layout so that the center differential lock is on a separate button or dial. No center differential lock button on the 1999-2000 4Runners 4WD Limited, the center differential is locked by moving the J-shifter to the H4L position, which also means you cannot have the center differential unlocked in 4LO. Some later models with the center differential button can be in 4LO with the center differential unlocked. The 2003 + 4Runners/GX, and Sequoias (not the Land Cruiser 100 series) has the same type torsen center differential mentioned in the video. Just the V6 4th gen 4Runners and the Sequoias have the multi-mode 4WD which allow you to switch between 2WD, 4HI, and 4LO. The best engine/driveline combo was the multi-mode in the 08+ V8 Sequoias since it was the only model that retained the multi-mode after 2008 plus it can be paired with the 5.7 V8. So IMO, Toyota/Lexus gimped the 5th gen and 6th gen 4Runner 4WD driveline a bit back in 2010 when they had a great working multi-mode and full-time 4WD but went cheaper to a part time system to save a couple of bucks. Luckily, the higher end trims and models such as 4Runner Limited, GX, LX, and Sequoia retained the full time 4WD. If they just retained the 08+ Sequoia multi-mode on all their 4WD models, it would have commonality (buttons, shifters/dials, parts, etc) across all their 4WD vehicles instead of having different part time parts and full time parts. That would probably saved a bunch on money and efficiency.
@@runnerxa so my "full-time 4WD" 1999 was totally open center diff and theoretically capable of a one-tire-fire in 4WD unlocked mode? That's pretty lame. It's definitely nice to have a lot of modes available. But if I'm going to have "full time 4WD" in a truck, I want it to limit how far the power split can vary front/rear. I certainly don't want 0/100 to be a possibility when I'm in any 4WD mode. I like getting back to the simplicity of the 2023, but it's also woefully unprepared for "half snowy, half dry" mountain roads in winter.
@@thatoneotherotherguy Yes. It actually happened to me before hence why I researched on my 1999 4Runner's AWD/full time 4WD capability/limitation. My GX/LX has the torsen based full time 4WD and functions much better than a fully open center diff.
Two truly amazing mechanical systems! To be able to draw it up and explain it is one thing, and Jason did a masterful job, but to actually conceptualize this from scratch in your mind, draw it up and then have it manufactured and work to perfection like it does completely blows my simple mind! I have an '03 Toyota 4Runner, V8, AWD, which I don't off road, so I don't really take advantage of it's full capabilities, but it's nice to know it's there (for some reason).
My old Jimny survived 34.000km... my new Jimny survived 45.000km and now needs a fully new transmission and underside... My RAV4 has 356.000km and needs new oil and brake pads... Real life experience and no yt bs 😊
As a GX 460 overlander I found this video extremely enlightening. I haven't found a need to lock the center diff on any of my travels but there may be some situations that even ATRAC can't figure out and you just need to route power to the wheel with grip
I had a 4th gen 4runner with fulltime 4WD system, and I recently sold it and switched to a Tacoma. I miss the fulltime 4WD more than I expected. I just got back from some rock crawling, and the part time system binds up a lot more on rocks. With the 4Runner I would occasionally need to lock the center diff when I needed maximum traction, but I could leave it unlocked most of the time. On snow I could compare locked and unlocked side by side with the 4runner. Unlocked is a huge improvement in handling. It would always go exactly where I wanted. With the center locked it would understeer because of the locked axles. As far as I know, no one on the 4th gen 4runner forums ever measured a significant difference in gas mileage between 2WD and 4WD unlocked. So there's probably no compelling reason to have a 2WD mode with Toyota's fulltime 4WD system.
Small correction Jason, the v4f transfer case in the 200, 150, 120 and 100 series does allow for low range without center locking. My gx470 does this. It's very handy for tight trails sure, but it's REALLY handy for trailering. I have to back a 24 foot boat into a tiny garage uphill on gravel and low range center unlocked is like a cheat code for doing it.
Nah, this is like as simple as it can be without removing further capabilities. There’s so little that can go wrong in them (provided regular fluid changes).
This makes me miss my 2008 V6 4WD 4Runner (RIP): 2WD, unlocked 4WD using a center Torsten differential, locked 4WD high, locked 4WD low. And it was standard equipment!
The Jeep Cherokee (XJ) and Liberty (KJ) offered either a part-time (NP231) or full-time (NP242) transfer case. While, yes, the full-time is more capable for overall driving, with more moving parts, under heavy use (for example running larger tires and driving it hard off-road), the NP242 was more susceptible to failure. But for normal driving, I would go with the full-time option, if available, and you can afford it. Excellent video, btw.
I think they fear too many people would bust the CVs using it. You have to be gentle. Ford has it in their Ranger Raptor so maybe we’ll see that in a Toyota one day.
I got my 4th Gen V8 4Runner years ago after totaling my 3rd Gen because I lost traction when I wouldn't have if it was fulltime. Never giving this one up. It just makes far too much sense in Colorado and hasn't let me down once.
Perfect timing for this video. I’m in the airport waiting for a flight home from Madagascar. So many people have 4WD and Land Cruisers. I don’t see Land Cruisers in the USA, only 4Runners. I was curious about the difference and found this video and it only came out 2 months ago!
In Qatar the Land Cruiser is basically the national car, almost every citizen has got one (though people are now going for the Lexus equivalent as well these days). Never seen one in the US. I see it is on their US website now (maybe recently brought to the US?, I thought it wasn't before because of emissions)... The US model is a 2.4L 4 Cylinder i-FORCE MAX Hybrid Powertrain 326 hp @ 6000rpm In Qatar they used to have V6 and V8 models. The current model is only V6, but 3.5 or 4.0 liters. The 4.0 liter actually being only 271 HP while the 3.5 liter is 409 HP as it's a twin turbo while the 4.0 liter I think is naturally aspirated. Found data quickly for one model year with V8: the 2019 Land Cruiser 5.7L V8 engine is equipped with 381 hp.
This helps - I ended up needing to get a 4Runner during Covid, and the only one that didn’t have have 25k markup tacked-on was a 2WD version which we got ( and love ) but I will replace it with a 4WD LC or 4Runner in a year or two. I was trying to get to make sense of Toyotas 4WD options between the two but this made it dead simple
Excellent video, it helps one to visualize all the limitations of the system and losses in the system compared to a EV powered 4WD system where all 4 wheels have individual motors, or one set of motors powers a separate set for the front or back. Very nicely done! Will help to settle a lot of debates I have with EV 4WD vs Mechanical 4WD (usually Gas powered). 😀
I really love the torsen differential - gives you very good stability for daily driving in different conditions. Part time 4wd is a bit annoying when roads are a bit icy but not icy enough to keep 4wd one consistently.
The Land Cruiser Prado 90, which could be called the great-grandfather of the Land Cruiser 250 mentioned in this video, came out in 1996 with full time 4wd and uses a planetary gearset for the center diff locked via splined shift ring, otherwise this diff was open. Some had that motorized, but most with a shifter. The 90 was followed by the Prado 120 (2003) and the Prado 150 (2010). Cant remember exactly but I believe one of them got the Torsen center diff at some point. The 120 had mostly shifter acuated center diff lock, but the VX versions had it motorized with the transfer case shifter only 4H-N-4L. The Prado 150 (at least in Europe) did away with the shifter for the transfer case and it is only button operated (motorized) and the brakes can assist with wheel-spin. So some of this tech is almost 30 years old, just FYI :) And one funny bit. The Prado 90 was called the Land Cruiser Colorado in the UK for some reason. And one more thing. I believe the 3rd Gen 4Runner Limited over a short period in the US had a transfer case that no other vehicle had, 2WD-AWD-4WD-4WDLO Correct me if I am wrong.
Yeah I think it was the 01/02 that had the weird tcase, I have one. It isn't the J-shift case, but you leave the tcase shifter in 4hi and engage a button on the shifter to go to unlocked 4hi (awd), then if you press the dash center lock it will be in 4wd locked, then shift to 4lo locked or unlocked, based on if center diff lock is engaged.
Brilliant explanation. We have owned a number of true 4x4 vehicles over the years but I often wondered how they were different to the part time versions. Your video has helped me to understand some of those differences. Many thanks for all your efforts as well.
I have a 2005 Lexus RX330 with open diffs, and I also have a 2007 Lexus RX350 with LSDs. From 2004 to 2009, the Lexus RX had full-time four-wheel drive systems. I've been through 2 snow storms where I brought a Lexus RX in for servicing, and they normally give me a new Lexus RX to drive while they are servicing my older Lexi. The drive through slush is confidence inspiring with my older Lexi, but not with the new front wheel drive/all wheel drive Lexus RX's.
I was just scratching my head over these questions a few days ago because I wanted to understand how my daughters 2010 4runner limited full time 4wd system works. You are Johnny on the spot! As to what is the difference between AWD and full time 4wd...your next video idea!
The difference is the locking ability and low range. Take those two features away, and you have Audis famous quattro system which also uses a torsen center diff. But generally speaking for other systems Full-time 4WD is AWD untill you lock the center diff.
@@rangerover06sc So, is the difference between a Toyota AWD and a Subaru AWD the amount the center diff sends front and rear, with the Toyota being 100% front until slip is detected and the Subaru being more of a 50/50 split at all times?
@Mach141 Well, if you're talking the clutch based active AWD systems, then yeah Toyota systems are by default 100% front and the Subaru system targets a 60/40 torque split. But the other AWDs found in manual Subarus or the WRX STI use a true full-time system with conventional geared differentials
I feel like I am back in College, where yet again I only understand about 5% of what is being said. Great video! I appreciate having a better understanding of the differences.
Ok, this is what I understood and I hope I am right. Please correct me if I'm wrong: - open diff has limited torque split but has no speed binding on paved surfaces - locked diff has unlimited torque split but has speed binding on paved surfaces if you lock a diff and force wheels to rotate in different speeds it may get broken opening the diff allows for different wheel rotation speeds.. so it's good for driving on high speeds with cornering locking the diff locks the speed but allows variable torque delivery when needed so it's only good in low speeds
Fantastic video! Thank you so much. I definitely learned new things from it. I drive a 2002 Jeep Grand Cherokee V8 with full time 4WD. I never fully understood how it worked or how it compared to the 4Runner’s part time 4WD system. Now at least I have a basic idea of what’s going on.
Always enjoy your videos, this one I think you had some areas where further explanation could be warranted. Around 6min-10min - throw in some graphics, or reference some info on how a clutch plate works. Still love your stuff. More Crosstrek content!
Thanks for the insights and I agree with your conclusion. I love my F-150 but I don't love having to turn the 4WD on and off with varying snow conditions from one street to the next. I think the 4WD makes sense exclusively for trucks that will be used off road extensively. .
I think the part-time system is the only one that supports a rear locker which is an incredible difference between the two systems that didn't get mentioned.
This is why I prefer the 4th gen 4Runner. The V6 has a transfer case with the ability to do 2WD or 4WD, but also has a Torsen center diff so you can run it in H4 all the time.
This was really helpful to understand the difference!! Thank you! I'd love to see you compare other similar toyota vehicles like Prius vs. Prius Prime or Camry v Corolla. The models appear so similar these days since they have hybrid engines and many/all trims now, but there are other mechanical differences that I'm sure you would explain well and help us determine which is best for whatever use case. I have a 2017 Prius. Great video!
Shout out to my fellow manual tacoma drivers :) yeah a 2wd-lo or 4wd open center diff option would be nice sometimes but usually works fine to just leave it in first gear in 2hi.
I like the way he explained that dark matter and I almost understood everything. If I have to explain it to someone else though, I'll stick to my version: The engine rotates some gears and then magic happens. The difference between full time and partial comes to one thing. Are you a Gryffindor or Slitherin fan.
Full-Time system shines in slippery conditions as in rain and in snowy roads. A little penalty is that you have carry this weighty system within a board all the time, and you have to pay attention at tyres equal air pressure so that it does not wear off Torsen clutch plates if differences turn out to be greater than normal allowed for engaging all the time.
We have a previous gen LC (prado as it is called in some places) at work and i have used 4-low without locking the center diff several times. There's a seperate button for center diff lock, which i have not needed yet.
@@Natures_DoctorFor 80 and early 100 series, that center lock button was there by default for use in 4hi. 4lo forced the lock unless you did the mod or had a later model year 100 series.
Just an FYI, there is a way to have 4WD Low without the center diff locked on the 100 Series and 80 Series Land Cruiser. It's called a Pin-7 mod. You simply remove the 7-pin from the ECU in the passenger footwell and that then allows 4 Low with selectable center diff lock. Works great. But yeah, definitely not factory configured.
Excellent video. It would be wonderful to have an explanation like this for every AWD system out there, It's too bad there aren't ten of you to do this. 🤣
The awd is superior, and basically the same as the oartiak time if you lock the center differential. In winter you have awd without the need to shifts to 4dw on and off in bad weather conditions. The only advantage the partial time system have is a slightly better fuel economy in 2wd.
The most important part is the locking of the differentials. LSD is good enough. Having the front wheels also locked tackles those last 1 or 2% of offroad situations. Our Terracan sure doesn’t have the most advanced system. Not even close, but only cars with tires that are not usable on road and/or have locking front wheels are better at driving through the forest with a couple of tonnes (+5000kg) on your trailer coupling. Still I’d like an unimog.
Not sure if its still the case, but in the 5th gen 4Runner 2010-2023 Toyota always fitted the full-time four-wheel drive Limited models with narrower tires to compensate for the efficiency losses. Those weird tall skinny wagon wheel yokohamas were 245/60R20. Great tire though.
Such a cool video! Thanks for bringing such quality content to this platform! This channel really blows my mind! You’ve gotta be one of the smartest guys on RUclips!
For towing, the low gear 4wd non locking centre diff is an advantage. Many years ago I bought a subaru forrester over a toyota Rav4 because of the low gear option in non turbo models, for towing.
FYI, The full-time 4wd system in the Lexus GX460, which has the same foundation as the 5th gen 4runner (Based on Toyota Land Cruiser Prado), Does allow the Torsen differential to be in 4lo open. The Lexus GX has always come with a center locker button that does not auto lock in 4lo. Why they didn't do/allow this in the 4runner is beyond me as I would assume they're the same transfer case (for the full-time 4wd models).
My GX470 can be unlocked in low range and there are several situations like technical but high traction, and sharp turns, where unlocked in low range shines.
I have a 2008 v8 4Runner with full time 4WD and I can be in 4lo (low range) without the center differential locked. I thought this could only be done with the newer full time 4WD system? Thank you for this video and the depth that you went into explaining. You should make a video explaining how Toyotas atrac system works.
I can lock it and unlocked it while being in 4lo as long as I’m in neutral. Also I’ve noticed that while being in 4hi I am able to lock and unlock it while in drive.
If there was a huge efficiency increase for the part time 4wd, there'd be an advantage, but it's pretty incredible the full time 4wd gets the mileage it gets driving 4 tires.
As a professional tech, I think you should cover a planetary gear set with a whole video of its own. Sun gear is its gear count, ring gear is its gear count, planetary carrier is the the effective gear count of the sun plus the ring. This arrangement based on one member input, one member held and the other output can yield underdrive, overdrive, forward, reverse. You should do a whiteboard video to describe the various applications of a planetary gearset itself on the automotive industry. I think so many laypersons do not understand the basic concept of planetary gears. The Toyota Synergy drive is probably the most genius/simple transmission ever designed. As a heavy truck tech, we have planetary wheel ends and 2 speed rear axles using planetary gearsets. I think the general public would greatly benefit from your explanation of how these gearsets work. Love your work! Keep it coming!!!
And torsen differential as well.
This please Jason!
I had to watch your explanations 4 times to minimally understand the mechanics of things here. (I'm not sure I fully did though... 😅)
I don’t understand what you just said
@@nachoismeexactly why we need someone to explain to our smooth little brains in video form
Was going to reply regarding the Toyota Synergy / hybrid transmission, and then you said it. Best “automatic” transmission I’ve ever owned. Stepless drive, and without a single clutch or brake pack or actuator to fail.
Even when I have no need to know the subject matter, in this case why 2 vehicles have 2 different 4wd, I like how Jason explains stuff… and painlessly stuff more knowledge into my brain.
Finally a good video combining all the knowledge into one. This is like hundreds of pages of 4Runner vs GX vs 200 vs Tacomas forums consolidated into one video.
The forums can be a great resource, but are truly a mess! I was thankful to have Toyota's engineers help with official documentation and questions such to sort it all out!
@@EngineeringExplained I also love how we have easy access to all the 4x4 chassis next to each other. Instead of having to rely on consumers to dig around and compare themselves!
Yep. Plus the torsen center differential with pretty much the same F/R ratios have been in use since 2003 in a lot of Toyota/Lexus full time 4WD vehicles.
LoL. Tacoma doesn't belong in the same sentence as a GX or 4Runner
Jason with Engineering Explained and Ryan at FortNine are two of the best teachers of both Automotive and Motorcycle Engineering on RUclips. Only difference is Ryan slides in some slick humour. Both are amazing at what they do.
Bro says I ain't got no jokes 😭😭
@@EngineeringExplained Ryan tends to push the sexual innuendo references, you are too busy explaining the tech. :)
Come on, Jason also tries the humor!
"knock knock" style, sometimes, but he makes the effort! 😁
This video was a straight mechanics lesson though... 😅
Tried watching a couple of the guys videos and couldn't tolerate him.
@@just.jose.youtube Jason has more a dry wit. Both are great in my opinion.
Fantastic explanation Jason! Well needed for the Toyota off-road community, especially the torque split misconception.
I don't understand the 0/100 or 100/0 scenario. Is 100 the grip side or the slip side? And why doesn't it work directly as 50/50? Can you help me?
Love your channel!!!
@@kamilkalfaoglu If the center diff is locked, the front and rear driveshafts must always rotate at the same speed regardless of resistance at the tires. So if the back wheels are up in the air and the front is on nice rough pavement, 50/50 would mean that half of the engine's torque is being used to spin the rear wheels. They're freely spinning, so 50% of engine torque would make them spin much faster than the front since the front has resistance to overcome. But a locked center diff can't spin the rear faster than the front, so a 50/50 torque split is not possible in that scenario. The front and rear driveshafts of a locked center diff must spin at the same speed, while only the front one is resisting the rotation. Hence virtually all of the engine torque is going to the front, because the back isn't resisting rotation. (Realistically, there is friction and rotational inertia so the rear tires will still require a little bitty bit of torque just to get them turning at the same speed as the front, so it's not quite 100/0, but it's close.)
@@jamieflournoy thank you so much. I understand right now. When I saw the 0, I thought that part wasn't turning despite the lock, but actually, it is turning but almost no torque is needed.
Is it just me or are other viewers excited when the white board gets revealed in one of these videos? I am always waiting through the intro to see what Jason has in store for me on the white board. This one is a GREAT one!
What many don't realize is that the 4th gen 4runner had everything available at its disposal, but only in the V6 models.
You could select 2hi, 4hi, 4lo. And since selecting the Torsen center diff was independent of whether it was in 4hi or 4lo, you could technically run in AWD Lo and never bind.
It was the best of all worlds, but my guess is Toyota had to simplify it because most people didn't understand how it worked. Many still get the new systems confused which have less to choose from.
They seem to go back and forth on it. 80 series locked the center diff in 4lo but you could mod it to not and everything would be fine.
Same for a period of time in the 100 series until they stopped and allowed you to do 4lo independently of locking the center diff without any mods.
Indeed! Love my 4th gen and all the options it gives me.
My 4th gen V8 lets me use low range with the center diff unlocked. So I get AWD hi and lo, and 4WD hi and lo.
@@MarkRose1337 Yep. I didn't mention the V8 in my original comment to try and keep it short. But it does everything the V6 does, except it can't go I to 2hi. I've gotten in so many arguments with V8 owners on the 4runner Facebook groups because they think just because the V6 has 2hi, it automatically means it's part time 4wd. (many V6 owners also think the same thing but don't necessarily argue as much in my experience 😂).
I boggles my mind why the non-Limited 5th Gen 4Runners did not have the center diff (like they did on 4th Gen). I’ve had 3 5th Gen Limited (since 2010). I would have liked at TRD ORP with KDSS, but since I live in New England, the AWD took priority…
I love this guy. He takes the incomprehensible and makes it almost understandable. 😁. Seriously, this is a great channel. Even in a case like this where the answer is obvious, it is fun to learn the reasons and understand why.
3rd gen 4Runners hsd a lovely multimode transfercase option. It was 4x2, push of a button gave you AWD open center differential that waa shiftable into AWD low range which was extremely handy backing trailers with surge brakes up steep driveways and thrn you could lock the center differential for a true 50/50 locked center diff in high or low range. This option was carried over into the V6 4th gen 4x4s and then disconnected for the 5th gen.
The manual shifter for the transfercase in the 5th gens are perfectly fine and less likely to go wrong. I'd choose mechanical over electronic anyday. You just have to hold them in for a few seconds with pressure to make sure it properly engages.
@@username8644 3rd gens only had a mechanical shifter.
@@CACressida You said, "push of a button". That's electronic.
@@username8644 third gen 4Runners have an AWD shift actuator as well as a mechanical J shift and LC style fore and aft transfercase style. The J shift tcase you see ina 5th gen is straight out of the 3rd gen 4Runner parts bin.
@@CACressida I see. Good to know.
In South Africa, the Landcruiser only comes with a 2.8 litre turbodiesel engine, also found in the Hilux. It's got something like 500 Nm of torque from as low as 1200 rpm. It's awesome!
Our eco-leftist bureaucrats won’t all US citizens to have consumer products with which the regime disagrees.
@@leonardc1303 the absence of the LC 75 has less to do with emissions and more to do with crash test safety regulation and the government not having a classification/exemption for basically 'specific purpose vehicle which sacrifices safety for a certain application'. The LC 75 could absolutely be made emissions compliant (maybe more emissions equipment on the diesel, maybe swap diesel for 5.7 gas), but it absolutely cannot be made modern crash test compliant without an exemption/new class of road vehicle being created with lesser standards.
I would love to have the diesel set ups yall have over here .
I just can't do the right hand drive cause I drove I r h drive jeep once and I kept stopping at people's mail boxes
Same 2.8 litre D-4D turbocharged diesel engine is used in the Toyota Fortuner as well, which produces 550 Nm of torque along with 221 bhp of power. Diesel SUVs are an emotion.
@Ab10i That's correct. The only downside to these engines are the piezoelectric injectors that are super expensive when they need replacing.
My 2004 4Runner has full time 4WD. It's nice in winter when the road is alternating between snow and bare. It handles better in most situations with the center diff unlocked and I've only used the center diff lock a few times where I needed it.
I have the same thing and totally agree. I love it for winter driving. I’m about to order a Tacoma and only the Limited model can come with this AWD/4WD setup with Low Range and Center Difflock. It’s a great system. In extreme off-road, I think the Rear Differential Lock in an Off Road Model prob works just a bit better though.
As you mentioned, the 4-runner Limited model has exactly the same full-time AWD and locking center differential as the land cruiser. I trade in every 2 years and stick with the limited edition and I am nearly always off-road in Florida (sugar sand and mud) and it never lets me down. Best production off road vehicle you can buy IMO. Jeep doesn't even stand a chance against them for reliability and features.
This is actually an amazing video; I've always wondered about how AWD/4WD is implemented and if you extrapolate from this video it really makes a lot of sense.
Really appreciated the no-slip torque split explanation; I always wondered how that's implemented.
Great explanation of a complex problem. As a side note, I have been driving my 2008 4Runner (RWD SR5) for over 15.5 years and it always gets 20.1 mpg in the city (with a light foot on the gas and stock 17" tires). I live in NE Iowa and it has gotten me through the worst snow storms ever with no problem. Sometimes a simple system can be the best choice.
The Toyota full-time system with the Torsen center differential is phenomenal. I have owned a 2011 GX460 and now have a 2018 LX570 and love this setup.
My favorite part is the ability to put it in 4Lo with the center diff unlocked. It make parking and maneuvering my 5500 lb trailer super easy without binding.
The fact that Toyota has not expanded this system in this new generation of trucks, particularly not putting it into the Tundra, and completely removing it from the Sequoia(which had full-time since it came out in 2001 MY) is very disappointing.
Totally agree! Also you can drive like a hoon in the rain and never loose grip (much). Having a locked centre can also cause understeer on loose gravel roads. I bought my 2014 Prado specifically for the AWD after coming from a long line of turbo Subarus.
@@peejay1981 that may explain why my old ST185R Celica GT-four was a (much) more understeery pig on gravel than my 4WD Corolla wagon of ~identical age. If my memory is right... the Celica had a centre diff that locked up on acceleration, and the Corolla did not.
@@mediocreman2 Make sure you specify which Subaru you're talking about. My BRZ has a Torsen LSD standard. It's not the center as the BRZ is RWD, but it's still a Torsen.
My 2007 FJ Cruiser 6-speed manual has the same torsen diff. Pretty cool stuff
Dude... Next level explanation & top shelf presentation! My favorite YT channel for years and continues to up the game. So impressive.
Thank you thank you thank you! Really appreciate the kind words, thanks for watching!
4th gen 4Runner used this version of full-time 4wd on the V-8 models and the V6 4wd models also came equipped with a torsen center diff as well but it was a part time 4wd system.
I finally understood torsen differentials, what a great video 👍
An extra bonus of full time systems for reliability is that you don't have auto locking hubs which are known to be failure points on a lot of vehicles. On my 100 series I can just push the center diff lock button while driving and it goes on/off almost instantly like an air locker would, no doing the forward/neutral/reverse dance that I've experienced on newer Tacomas. Obviously shifting between hi/low range requires you to be stopped and in neutral but it's also a straight throw lever and super smooth.
I don't know about newer Tacomas but with my 2013 I believe the hubs are permanently locked. The 2wd vs 4wd selection happens at the front diff so no forward/reverse dance is necessary.
*eyes glazed over*
appreciate all the time and effort for this explanation -- but holy cow that's a lot
that's why i love my Mitsu Shogun. Great explanations, Jason, as always.
Now this is the content I want to watch. No fancy stuff like the other videos but clearly explains how this work. Well done!
It was great to see your inclusion of the Car & Driver article. I've always loved the way they break down automotive tech. Which, come to think of it, is probably why I really like your videos.
This was a SUPER helpful video. I have a 2023 4Runner with the part-time 4WD system. I always wondered how the full-time 4WD Limited models did it differently. I had no idea a Torsen diff (or at least this particular one) was a planetary gearset. I had a '99 Limited 4Runner with a fancy transfer case that ran the full gamut from 2hi, 4hi part time, 4hi full-time, and 4lo, I wonder how that got it all done.
We also own a 2023 Outback. After this, I went back to your seven year old video on Subaru AWD systems as a refresher. There's so many different ways to do this! I wonder if an update on the Subaru video would be worth it? Looks like they no longer offer two of the four systems shown in that video, and I wonder if they've changed functionality at all on the latest generation stuff.
And finally, ALL of these systems seem so complicated compared to just independent dual-motor AWD on most EVs. I look forward to electric offroading once it arrives in more mainstream, smaller models.
The 1999 had the VF3AM transfer case which has a center differential in it. It is not a torsen differential that can change the ratio if slip is detected while in 4HI - (center diff) unlocked. It is just an open differential when run in 4HI - unlocked (J-shifter in H2-H4 with the 4WD button pushed in). Nomenclature wise, the 99-00 4Runners 4WD Limited does not have 4HI part time, it is 4HI - (center differential) locked with the J-shifter in the H4L position, which locks the front & rear just like a part time 4WD. 2001+ 4Runners and subsequent multi-mode J-shifter changed the layout so that the center differential lock is on a separate button or dial. No center differential lock button on the 1999-2000 4Runners 4WD Limited, the center differential is locked by moving the J-shifter to the H4L position, which also means you cannot have the center differential unlocked in 4LO. Some later models with the center differential button can be in 4LO with the center differential unlocked. The 2003 + 4Runners/GX, and Sequoias (not the Land Cruiser 100 series) has the same type torsen center differential mentioned in the video. Just the V6 4th gen 4Runners and the Sequoias have the multi-mode 4WD which allow you to switch between 2WD, 4HI, and 4LO. The best engine/driveline combo was the multi-mode in the 08+ V8 Sequoias since it was the only model that retained the multi-mode after 2008 plus it can be paired with the 5.7 V8. So IMO, Toyota/Lexus gimped the 5th gen and 6th gen 4Runner 4WD driveline a bit back in 2010 when they had a great working multi-mode and full-time 4WD but went cheaper to a part time system to save a couple of bucks. Luckily, the higher end trims and models such as 4Runner Limited, GX, LX, and Sequoia retained the full time 4WD. If they just retained the 08+ Sequoia multi-mode on all their 4WD models, it would have commonality (buttons, shifters/dials, parts, etc) across all their 4WD vehicles instead of having different part time parts and full time parts. That would probably saved a bunch on money and efficiency.
@@runnerxa so my "full-time 4WD" 1999 was totally open center diff and theoretically capable of a one-tire-fire in 4WD unlocked mode? That's pretty lame. It's definitely nice to have a lot of modes available. But if I'm going to have "full time 4WD" in a truck, I want it to limit how far the power split can vary front/rear. I certainly don't want 0/100 to be a possibility when I'm in any 4WD mode. I like getting back to the simplicity of the 2023, but it's also woefully unprepared for "half snowy, half dry" mountain roads in winter.
@@thatoneotherotherguy Yes. It actually happened to me before hence why I researched on my 1999 4Runner's AWD/full time 4WD capability/limitation. My GX/LX has the torsen based full time 4WD and functions much better than a fully open center diff.
You are too good at this bro.
Two truly amazing mechanical systems! To be able to draw it up and explain it is one thing, and Jason did a masterful job, but to actually conceptualize this from scratch in your mind, draw it up and then have it manufactured and work to perfection like it does completely blows my simple mind! I have an '03 Toyota 4Runner, V8, AWD, which I don't off road, so I don't really take advantage of it's full capabilities, but it's nice to know it's there (for some reason).
My old Jimny survived 34.000km... my new Jimny survived 45.000km and now needs a fully new transmission and underside...
My RAV4 has 356.000km and needs new oil and brake pads...
Real life experience and no yt bs 😊
As a GX 460 overlander I found this video extremely enlightening. I haven't found a need to lock the center diff on any of my travels but there may be some situations that even ATRAC can't figure out and you just need to route power to the wheel with grip
I had a 4th gen 4runner with fulltime 4WD system, and I recently sold it and switched to a Tacoma. I miss the fulltime 4WD more than I expected. I just got back from some rock crawling, and the part time system binds up a lot more on rocks. With the 4Runner I would occasionally need to lock the center diff when I needed maximum traction, but I could leave it unlocked most of the time.
On snow I could compare locked and unlocked side by side with the 4runner. Unlocked is a huge improvement in handling. It would always go exactly where I wanted. With the center locked it would understeer because of the locked axles.
As far as I know, no one on the 4th gen 4runner forums ever measured a significant difference in gas mileage between 2WD and 4WD unlocked. So there's probably no compelling reason to have a 2WD mode with Toyota's fulltime 4WD system.
Small correction Jason, the v4f transfer case in the 200, 150, 120 and 100 series does allow for low range without center locking. My gx470 does this. It's very handy for tight trails sure, but it's REALLY handy for trailering. I have to back a 24 foot boat into a tiny garage uphill on gravel and low range center unlocked is like a cheat code for doing it.
Thanks for the correction! I was told by Lexus that it was a new feature. 🤷♂️
Keep same pace! I love that you get through a lot of content in as little as time as possible.
Hats off to you for this video!!! The level of detail and explanation really helped me conceptualize the differences in application and function.
This is exactly the info I needed to make an informed decision between the new 4Runner and which system to choose! 🤘🏼
How overengineered do you want your differential?
Torsen: YES.
I would say they are mechanically engineered to perfection, so that they don't need to be over engineered and use electronics.
Nah, this is like as simple as it can be without removing further capabilities. There’s so little that can go wrong in them (provided regular fluid changes).
Jason, You make understanding these subjects FUN! Thank you.
This makes me miss my 2008 V6 4WD 4Runner (RIP): 2WD, unlocked 4WD using a center Torsten differential, locked 4WD high, locked 4WD low. And it was standard equipment!
The Jeep Cherokee (XJ) and Liberty (KJ) offered either a part-time (NP231) or full-time (NP242) transfer case. While, yes, the full-time is more capable for overall driving, with more moving parts, under heavy use (for example running larger tires and driving it hard off-road), the NP242 was more susceptible to failure. But for normal driving, I would go with the full-time option, if available, and you can afford it. Excellent video, btw.
Jason you have provided an excellent explanation. Now Toyota needs to explain why they won't bring their locking front differentials to this market. 🤔
And what's going on with their current V6's....
I think they fear too many people would bust the CVs using it. You have to be gentle.
Ford has it in their Ranger Raptor so maybe we’ll see that in a Toyota one day.
I got my 4th Gen V8 4Runner years ago after totaling my 3rd Gen because I lost traction when I wouldn't have if it was fulltime. Never giving this one up. It just makes far too much sense in Colorado and hasn't let me down once.
The turbo/hybrid combo sounds like an absolute nightmare to work on when something breaks or wears out.
Perfect timing for this video. I’m in the airport waiting for a flight home from Madagascar. So many people have 4WD and Land Cruisers. I don’t see Land Cruisers in the USA, only 4Runners. I was curious about the difference and found this video and it only came out 2 months ago!
In Qatar the Land Cruiser is basically the national car, almost every citizen has got one (though people are now going for the Lexus equivalent as well these days). Never seen one in the US. I see it is on their US website now (maybe recently brought to the US?, I thought it wasn't before because of emissions)...
The US model is a 2.4L 4 Cylinder i-FORCE MAX Hybrid Powertrain 326 hp @ 6000rpm
In Qatar they used to have V6 and V8 models. The current model is only V6, but 3.5 or 4.0 liters. The 4.0 liter actually being only 271 HP while the 3.5 liter is 409 HP as it's a twin turbo while the 4.0 liter I think is naturally aspirated. Found data quickly for one model year with V8: the 2019 Land Cruiser 5.7L V8 engine is equipped with 381 hp.
Finally someone explained how 40/60 torque split is achieved. Thanks
This helps - I ended up needing to get a 4Runner during Covid, and the only one that didn’t have have 25k markup tacked-on was a 2WD version which we got ( and love ) but I will replace it with a 4WD LC or 4Runner in a year or two. I was trying to get to make sense of Toyotas 4WD options between the two but this made it dead simple
Excellent video, it helps one to visualize all the limitations of the system and losses in the system compared to a EV powered 4WD system where all 4 wheels have individual motors, or one set of motors powers a separate set for the front or back. Very nicely done! Will help to settle a lot of debates I have with EV 4WD vs Mechanical 4WD (usually Gas powered). 😀
I really love the torsen differential - gives you very good stability for daily driving in different conditions.
Part time 4wd is a bit annoying when roads are a bit icy but not icy enough to keep 4wd one consistently.
The Land Cruiser Prado 90, which could be called the great-grandfather of the Land Cruiser 250 mentioned in this video, came out in 1996 with full time 4wd and uses a planetary gearset for the center diff locked via splined shift ring, otherwise this diff was open. Some had that motorized, but most with a shifter. The 90 was followed by the Prado 120 (2003) and the Prado 150 (2010). Cant remember exactly but I believe one of them got the Torsen center diff at some point. The 120 had mostly shifter acuated center diff lock, but the VX versions had it motorized with the transfer case shifter only 4H-N-4L. The Prado 150 (at least in Europe) did away with the shifter for the transfer case and it is only button operated (motorized) and the brakes can assist with wheel-spin. So some of this tech is almost 30 years old, just FYI :)
And one funny bit. The Prado 90 was called the Land Cruiser Colorado in the UK for some reason.
And one more thing. I believe the 3rd Gen 4Runner Limited over a short period in the US had a transfer case that no other vehicle had, 2WD-AWD-4WD-4WDLO Correct me if I am wrong.
Yeah I think it was the 01/02 that had the weird tcase, I have one. It isn't the J-shift case, but you leave the tcase shifter in 4hi and engage a button on the shifter to go to unlocked 4hi (awd), then if you press the dash center lock it will be in 4wd locked, then shift to 4lo locked or unlocked, based on if center diff lock is engaged.
Brilliant explanation. We have owned a number of true 4x4 vehicles over the years but I often wondered how they were different to the part time versions. Your video has helped me to understand some of those differences. Many thanks for all your efforts as well.
I have a 2005 Lexus RX330 with open diffs, and I also have a 2007 Lexus RX350 with LSDs. From 2004 to 2009, the Lexus RX had full-time four-wheel drive systems. I've been through 2 snow storms where I brought a Lexus RX in for servicing, and they normally give me a new Lexus RX to drive while they are servicing my older Lexi. The drive through slush is confidence inspiring with my older Lexi, but not with the new front wheel drive/all wheel drive Lexus RX's.
I was just scratching my head over these questions a few days ago because I wanted to understand how my daughters 2010 4runner limited full time 4wd system works. You are Johnny on the spot! As to what is the difference between AWD and full time 4wd...your next video idea!
The difference is the locking ability and low range. Take those two features away, and you have Audis famous quattro system which also uses a torsen center diff. But generally speaking for other systems Full-time 4WD is AWD untill you lock the center diff.
@@rangerover06sc So, is the difference between a Toyota AWD and a Subaru AWD the amount the center diff sends front and rear, with the Toyota being 100% front until slip is detected and the Subaru being more of a 50/50 split at all times?
@Mach141 Well, if you're talking the clutch based active AWD systems, then yeah Toyota systems are by default 100% front and the Subaru system targets a 60/40 torque split. But the other AWDs found in manual Subarus or the WRX STI use a true full-time system with conventional geared differentials
Engineering Explained!!! Great piece of content thank you!
I feel like I am back in College, where yet again I only understand about 5% of what is being said. Great video! I appreciate having a better understanding of the differences.
The Tacoma Limited (as with the 4Runner) also has the full-time AWD setup.
And no rear locker. No thanks.
Ok, this is what I understood and I hope I am right. Please correct me if I'm wrong:
- open diff has limited torque split but has no speed binding on paved surfaces
- locked diff has unlimited torque split but has speed binding on paved surfaces
if you lock a diff and force wheels to rotate in different speeds it may get broken
opening the diff allows for different wheel rotation speeds.. so it's good for driving on high speeds with cornering
locking the diff locks the speed but allows variable torque delivery when needed so it's only good in low speeds
i love my 80 series cruiser 😄
Fantastic video! Thank you so much. I definitely learned new things from it. I drive a 2002 Jeep Grand Cherokee V8 with full time 4WD. I never fully understood how it worked or how it compared to the 4Runner’s part time 4WD system. Now at least I have a basic idea of what’s going on.
Always enjoy your videos, this one I think you had some areas where further explanation could be warranted. Around 6min-10min - throw in some graphics, or reference some info on how a clutch plate works. Still love your stuff. More Crosstrek content!
This is S-tier content we all love about EE 💯
Thanks for the insights and I agree with your conclusion. I love my F-150 but I don't love having to turn the 4WD on and off with varying snow conditions from one street to the next. I think the 4WD makes sense exclusively for trucks that will be used off road extensively. .
I think the part-time system is the only one that supports a rear locker which is an incredible difference between the two systems that didn't get mentioned.
4x4 in Low Ratio with centre diff unlocked is perfect for manoeuvring heavy trailers, especially when reversing tightly around obstacles.
Never really understood why my sequoia came with a torsion center locker. Thanks for the explanation on that 👍
These videos are so understandable, it’s hypnotic
Limited slip center diff WITH selectable lock? Awesome!
...just needs a lsd and/or lock in the front also. With lsd in the rear also.
This is why I prefer the 4th gen 4Runner. The V6 has a transfer case with the ability to do 2WD or 4WD, but also has a Torsen center diff so you can run it in H4 all the time.
This was really helpful to understand the difference!! Thank you! I'd love to see you compare other similar toyota vehicles like Prius vs. Prius Prime or Camry v Corolla. The models appear so similar these days since they have hybrid engines and many/all trims now, but there are other mechanical differences that I'm sure you would explain well and help us determine which is best for whatever use case. I have a 2017 Prius. Great video!
Thank you for the really detailed explanation. I got it even not being a transmission expert!
This was great. I've always wondered how these systems worked.
toyota has really stepped back into the offroad game
Shout out to my fellow manual tacoma drivers :) yeah a 2wd-lo or 4wd open center diff option would be nice sometimes but usually works fine to just leave it in first gear in 2hi.
Everything car related from you is a dream come true.
Transmission tech nowadays is arguably more complicated than engine itself❤
I like the way he explained that dark matter and I almost understood everything. If I have to explain it to someone else though, I'll stick to my version: The engine rotates some gears and then magic happens. The difference between full time and partial comes to one thing. Are you a Gryffindor or Slitherin fan.
Man that was really in-depth. I will have to watch again. I just bought the LC250
How are you liking it so far?
Full-Time system shines in slippery conditions as in rain and in snowy roads. A little penalty is that you have carry this weighty system within a board all the time, and you have to pay attention at tyres equal air pressure so that it does not wear off Torsen clutch plates if differences turn out to be greater than normal allowed for engaging all the time.
4-low in the old LCs without locking the center diff was certainly possible… just snip pin 7 off the t-case control module.
We have a previous gen LC (prado as it is called in some places) at work and i have used 4-low without locking the center diff several times. There's a seperate button for center diff lock, which i have not needed yet.
You can also install a center diff lock switch to engage the cdl in 4hi the connector is behind the dashboard
@@Natures_DoctorFor 80 and early 100 series, that center lock button was there by default for use in 4hi. 4lo forced the lock unless you did the mod or had a later model year 100 series.
Just an FYI, there is a way to have 4WD Low without the center diff locked on the 100 Series and 80 Series Land Cruiser. It's called a Pin-7 mod. You simply remove the 7-pin from the ECU in the passenger footwell and that then allows 4 Low with selectable center diff lock. Works great. But yeah, definitely not factory configured.
Excellent video. It would be wonderful to have an explanation like this for every AWD system out there, It's too bad there aren't ten of you to do this. 🤣
The awd is superior, and basically the same as the oartiak time if you lock the center differential. In winter you have awd without the need to shifts to 4dw on and off in bad weather conditions. The only advantage the partial time system have is a slightly better fuel economy in 2wd.
Talk about luring people into learning through thumbnail!!!! This deserves a like...😄😄 Very good explanation.
The most important part is the locking of the differentials. LSD is good enough. Having the front wheels also locked tackles those last 1 or 2% of offroad situations.
Our Terracan sure doesn’t have the most advanced system. Not even close, but only cars with tires that are not usable on road and/or have locking front wheels are better at driving through the forest with a couple of tonnes (+5000kg) on your trailer coupling.
Still I’d like an unimog.
Very very in depth video, you literally answered my biggest concern between the two.
Not sure if its still the case, but in the 5th gen 4Runner 2010-2023 Toyota always fitted the full-time four-wheel drive Limited models with narrower tires to compensate for the efficiency losses. Those weird tall skinny wagon wheel yokohamas were 245/60R20. Great tire though.
I love this channel. I always learn something new.
Thanks heaps for this excellent presentation!! Highly appreciated as I’m considering purchasing a Toyota 4WD soon ❤😎👍👍
Such a cool video! Thanks for bringing such quality content to this platform! This channel really blows my mind! You’ve gotta be one of the smartest guys on RUclips!
Great explanation of these systems! Also loved those clips of the chassis with drive trains exposed to visualize the various gearboxes too.
This is the answer I was looking for.
The Torsen system is great for fleet vehicles in remote areas as you dont need to worry about people doing the wrong thing.
Thank you because my wife and I are currently in the middle of deciding between these two vehicles.
For towing, the low gear 4wd non locking centre diff is an advantage. Many years ago I bought a subaru forrester over a toyota Rav4 because of the low gear option in non turbo models, for towing.
TLDR : Suzuki jimny wins.
Really nice system. Almost as good as an Isuzu Trooper TOD.
Great explanation of the systems. I taught automatic transmission principles and operation during my career. This was a good refresher course.
FYI,
The full-time 4wd system in the Lexus GX460, which has the same foundation as the 5th gen 4runner (Based on Toyota Land Cruiser Prado), Does allow the Torsen differential to be in 4lo open. The Lexus GX has always come with a center locker button that does not auto lock in 4lo. Why they didn't do/allow this in the 4runner is beyond me as I would assume they're the same transfer case (for the full-time 4wd models).
My GX470 can be unlocked in low range and there are several situations like technical but high traction, and sharp turns, where unlocked in low range shines.
I have a 2008 v8 4Runner with full time 4WD and I can be in 4lo (low range) without the center differential locked. I thought this could only be done with the newer full time 4WD system?
Thank you for this video and the depth that you went into explaining. You should make a video explaining how Toyotas atrac system works.
I can lock it and unlocked it while being in 4lo as long as I’m in neutral. Also I’ve noticed that while being in 4hi I am able to lock and unlock it while in drive.
If there was a huge efficiency increase for the part time 4wd, there'd be an advantage, but it's pretty incredible the full time 4wd gets the mileage it gets driving 4 tires.
excellent analysis. There are pros and cons to every design decision.
Finally, someone explains this using logic.