For 300km that trans is in pretty damn good condition. But yeah you should also do a tear down of the cvt. Subarus have some pretty solid ones and I’d love to see a rip down of one.
@@shakalpb1164 yeah thats one thing i dislike with all companies that are using cvt’s. The fake shift mimicking. Just let it be a cvt, everyone already knows it is so let it hold the high revs and push power
I've been into Subarus for 20+ years, and this is the best teardown of a Subaru transmission I've ever seen. Would love to see an STI transmission, or at least the front diff.
It’s amazing the amount of engineering that must go into designing transmissions like these! Just the tear down with all those clutches makes my head spin!
@speedkar99 same as computers. Those are on the different level of complexity, but you can still understand the basic architecture and how stuff works.
Subaru AT VTD system is pretty ingenious. I recall when I owned my Impreza I could feel torque shifting between the front and rear axle when I was driving on a snowy frozen lake. Cool stuff.
That's cool! From what I understand the torque split isn't that different between the front and rear wheels, probably 40/60. Interesting that you could even feel that much.
From someone who’s driven Subarus all their life and now drives a Mitsubishi Triton for Work , let me tell you I have taken Subarus traction and control on the road, especially in wet weather for granted!!!!! These new two wheel drives, front wheel drive or rear wheel drive, on a hill slight bit of rain, and you just slide everywhere. Subarus control is unprecedented, taking into account the small increase in fuel consumption, and lack of being able to switch between two wheel and four wheel. They’re amazing
How would you guys know? This video is about the most uncommon. by far, Subaru AWD, the VTD. Variable Torque Distribution -- the most premium AWD system that Subaru ever made, and not cheap. You don't get this expensive piece of kit in a Crosstrek, Forester or Legacy. Ha ha. Dream on if you think so. Relatively, very few VTDs were made, fitted mostly to Legacy GT and H6 models until 2016 -- but only with the automatic. One version that worked with manual transmission was fitted to all STIs and Legacy Spec B cars with the real heavy duty 6-speed manual transmission -- you'll never find that tranny in a mere WRX. The manual transmission many choose in a WRX has a regular gear centre differential, with an all but totally useless viscous limited slip can of wonder-juice hooked between front and rear axle outputs. Its torque rating is only about 30 lb-ft or 40 nt-m. And that only happens when there's hundreds of rpm difference between the shafts to front and rear axle, and the special fluid actually then heats up enough to lock up the plates to transmit a reative drip of torque. Like, when does that happen? Almost never. Viscous limited slip is just about useless in practice. In cars. And many rubberneckers, no doubt including many viewers, think a viscous unit is a differential! How uninformed can people be? Completely, I'd guess. The unit is there for JDM specmnship and does not do much at all. And, by the way, AMC had the Eagle for 1978, and it had a gear centre differential with a viscous limited slip with a better torque rating than Subaru ever had 15 years later. The unit was made for AMC by Chrysler's New Process Gear Division. So VW/Audi were handily beaten to quattro by Detroit. Roy Lunn led the AMC design team -- google him and learn something. Nobody here knows their historical stuff, it's obvious. Most Subaru AWD systems are the cheapo MPT system. Multi-Plate clutch, first came out for the '88 model year. Compared to a Haldex, the only difference was that, instead of disconnecting the MPT clutch entirely from the drive to the rear axle when not needed, Subaru chose to make a guess and allow springs to give about 10% torque to the rear wheels at all times, so the clutch never fully disengaged. And "Symmetrical AWD" was born in the marketing man's mind. It's hooey. Subaru upped that initial force to 40% of some theoretical number for the '99 model year. All pure guesswork. Because, simply, the tires make the axles turn at the same speed anyway, so the clutch almost NEVER has to slip much and overheat -- '90s Subarus centre clutches rusted solid together, and you had to do a violent reverse 90 degree J-turn to unstick the plates! Saw the chief mechanic doing that many times at my Audi/Siubaru dealer. Mrs Smith would come in complaining about juddering when she parked and had to do tight turns. Well, rust acted just like my first quattro's centre diff lock, and made those automatic MPT Subies full time 4WD. It's how this more typical Subaru MPT AWD and that updated Torsen C system in later Audis get by with such a drippy, not very strong clutch -- hardly ever has to actually DO anything, like slip much and generate heat. I'm a retired mechanical engineer. I have owned an original '86 Audi quattro, an '88 Subaru GL Turbo with the first MPT AWD system, a '90 Eagle Talon AWD turbo, a '94 Audi 90 manual with Torsen centre diff, a '99 Impreza with MPT, and an '08 Legacy GT with the exact transmission and AWD system you tear apart here in this video. My considered opinion, after having watched a few of your videos is that you do a very poor job of explaining anything. You talk too fast like carny barkers, skip over most everything, and seem clueless. To me, at any rate. Nobody could learn anything from this once-over-lightly nonsense of a non-explanation, far as I can tell. And the comments reflect that, frankly. The viewers haven't learnt a thing either. Maybe you think you know what's going on, but I'd bet you don't most of the time. Unless you are mechanical savants, and not just guys with a machine-gun delivery style and full of blarney and gift of the gab. In my opinion, of the six AWD cars I've owned, the best in awkward conditions was the '94 90 Quattro, followed by the Subaru VTD in the Legacy GT. Then the Talon, then the original quattro in diff-lock mode. The Subaru MPTs were obviously FWD by comparison, and their drive to the front wheels is permanent anyway. The '94 90 Quattro was an understeering pig of a car with a very lazy V6 engine that could hardly pull the skin off a rice pudding. Overall, I did not like it except in sbow and on ice. So, to me, when you say Subaru symmetrical AWD explained in the video title, and then you pick Subaru's most sophisticated and expensive AWD system, and NEVER mention that it's hardly typical of the average Subie, thus giving your average plodder of a viewer entirely the incorrect impression of what resides in their Crosstrek chariot, yo have done them a big disservice. Argue your way out of what I know to be true if you can. I am NOT impressed,. Because this video isn't close to explaining anything to anyone, in my considered opinion.
Subaru engineering on their drivetrain system is top of line. What their cars are capable of is simply incredible. Another well made Japanese based product
@@brandonsmith3447 Plenty of NA EJs kicking around with high mileage. Especially early 90s dual port EJ18s and 22s. Seen a few EJ251s and early non-avls 253s with over 400k on them. Are they Toyota RZ (4cyl out of early Tacomas/T100s) reliable, no, but far from the worst things you could buy.
A lot of thought went into the engineering and design of this transmission. A lot. Makes me appreciate the amount of planning and execution to make all this happen in one unit. Integrating the front differential with the transmission makes perfect sense and saves space too. The next time I see a Subaru on the road. I will go out of my way to smile and wave at the owner because quite frankly they absolutely deserve it.
Dang, great video explaining this complicated Subaru AWD Engine; what a beauty, so that's why they're so good on rough terrain, and durable and expensive
@@speedkar99 Really Well designed, the only that I don't like, is the price, but I guess it's worth it. This is for Wagons/SUVs right, not cars/hatchbacks?
Just came here because I was getting torque converter codes on my '13 Crosstrek and wanted to understand the whole transmission system better before I took it in. Thanks so much for your breakdown and explanation. This video was amazingly helpful to get a little education and I feel I will definitely be to better understand what the service mechanic tells me about the issue I'm having.
You Sir, are magnificent, And your videos are about as in-depth as it possibly gets. thank you soo much for giving me the knowledge of the automotive world.
Amazing, how engineering mind comes to these ideas/designs, then even more amazing is how the production is quickly designed to make the parts in volumes from the drawings to the tooling and most amazing is how in a few years a completely new model gearboxes are out and all starts almost from the scratch. But one thing I am sure is you can never put it back together again (11:41). Very nice presentation (as always) and showing how we take things for granted. When the average person buys the car, get the keys and starts the engine the last thing on his/her mind is the complexity of parts that allows us to drive it the way it is designed for. Your videos will always change the way we look at the car machinery after watching them. There is an old Chinese proverb from 500 BC (maybe philosopher Confucius?): “I hear I forget, I see I remember, I do I understand.” Well your videos are the bridge between see and do. Not only we see it but almost like as we did it ourselves. But not only that, many times you through into your videos some facts from statistics or experiences you will not find in manuals especially when you talk about good or bad things in design or manufacturing. So thanks for doing these videos and sharing with everyone. I hope you get enough financial support to continue doing what you are doing but even more for your wife and brother. I hope they will never run out of money for their new clothes and underwear. And toothbrush.
I am very thankful for your feedback. I'm glad that people can benefit, just as I do when I learn as I tear things down. I didn't learn any of this in engineering school.
12:15 I don’t think those are “sun” gears with “step-down planet gears” around the input and output shafts, that you might see with a ring gear. To me those look like they are functioning as differential side gears, going around together with both shafts until there is a difference in speed. Which is also why there are so many!!
5EAT with the VTD system. It's actually a WRX AWD system with no adjustment. That clutch pack in the rear by the *Torsen* center diff is actually to alter the torque split from 45F/55R to about 50/50. Even if it wears out completely, you still have 45F/55R.
The 2015+ WRX CVT uses this style center diff, not the 5spd nor split case WRX 6spd manual. The VTD center diff is actually a Planetary Gear differential. A Torsen would apply friction to limit slip. The VTD clutch pack limits the slip.
Just so you know: an open diff is a constant 50/50 torque split. People often confuse that. An lsd or in this case the clutch pack allows the torque to go to the wheels that have the most traction. Therefore, when the diff is locked, it’s not a 50/50 split but a xx/xx split, meaning it changes dynamically. If both front tires are on ice and both rear are on asphalt, 90 something percent of the torque will go to the rear with the diff locked.
I understand your point. I sometimes get confused between torque and RPM. Also this diff is technically 45/55 seeing the difference in the size of the sun gears driving the output shafts.
Great video! Awesome to see the inside of the valve body. First time seeing the combination planetary gearset + clutch for me. I am more familiar with the 4EAT which IIRC are full-time FWD with a clutch pack that can send some power to the rear (or fully lock like a transfer case).
@@avsti Correct. If the clutch packs aren't active, the system will be like a basic all time 4x4 with centre diff. Much closer to the manual transmissions than the 4EAT.
The trick to cutting with a cordless grinder is to use the thinnest cutoff wheel you can find. 1/16” or 1/32” works well. But no matter what they are power hungry.
I’ve owned Subaru outback for years I think they’re the best car ever thank you for this video not that I am that capable but I often wondered how it all worked with the gearbox thank you very much indeed you’re a clever man😊
I have a 2001 Outback LL Bean with the H6 engine. My understanding is that the transmission logic is as follows: * In first and second gear, the differential clutch is actuated hydraulically and there is a 50/50 torque split. Always. * In third and fourth gear, the computer releases the clutch such that 90% of the torque goes to the front axle and about 10% goes to the rear, simply to reduce drag/increase fuel mileage. * In third and fourth, the system monitors front and rear axle speeds, and if the front axle spins faster than the rear, then the clutch is progressively engaged until speeds are equalized. It can operate the opposite way to reduce rear axle speed as well. * Both axles use limited slip differentials to control side to side wheel speeds. The VDC cars work totally differently, and have no limited slip differentials, they use torque vectoring in order to provide stability control and the center differential is totally different. They can also give 50/50 torque splits in higher gears. This system is similar to the system in the STI's. At least that is my understanding....YMMV.
Thanks for your input, it makes sense at higher gears and thus higher speeds, the front wheels are mostly powered, similar to other crossover type vehicles
Thanks for your effort . Mrs has a 2012 Outback 3.6r with that trans . I am a retired auto tech but did most of my work on Fords . I you pull the plug on the pan you get 4 qts out of it . I have been changing just 4 qts every 20000 miles . Trying to make the car go as far as possible . Those clutch packs look good for the mileage that unit had .
I find the variety of differential and transfer case types to be extremely interesting. Plated diffs with electromechanical control, or electrohidraulic, or electromagnetic, or gerotor pump, geared lsd's, center diffs for transverse engines, torque vectoring diffs with or without spider gears and planetary gearsets This VTD subaru is one of their finest, at first it was viscous, later it switched to electro hydraulic. Lexus GS has a similar system before 2007, with planetary open diff with plates, after 2007 they switched to a torsen C fully mechanical diff
Not often you see a Subaru 5EAT taken apart. I wished they ran a 4.111FD instead. I also wished Subaru put the VTD center diff as standar across the model line up. It's a much better AWD system. Your average non-car person wouldn't know the difference between the multiplate transfer clutch VS this VTD center diff. Awesome video!
I am a bit technical. But not even close enough to fully understand how all this system of levers, gears, clutches... works. Still, I drive a Forester. So thank you so much for the video!
Great vid! If I ever have the misfortune to use the wealth of information, I'll def come back! The best itip I got out of this was the extended socket to avoid the mess when removing the oil drain plug. Thank you!
I can easily follow along & understand how an ice engine works & what all the parts are doing. I understand how a clutch & fluid torque converter work. The fluid torque converter itself is pretty genius. In how how they were able to use fluid & centrifugal force. To move the weight of an entire car with no actual mechanical shaft connection from the engine to the transmission drive shaft. But when in it comes to transmissions with all the gears, parts, valves,etc.. It boggles my mind trying to folliw along & fully grasp how all those parts work together & exactly what's going on inside.
@@speedkar99 Plus trying to visualize how all the fluid travels around in the worm tray & trying to visualize what's happening in the valve body....I think the fluid changes directions and travels in different paths in the worm tray depending upon what gear it's in & how fast different shafts are spinning. But it's still mind boggling & I don't understand how someone can fully grasp everything that's going on inside......🆚 something like a jet turbine that's pretty easy to fully grasp how it all works.
Incredible video and explanation, had 6 Subarus manual and autos now. Love my 5spd AT behind the flat 6, incredible engineering. If you have a Subaru I highly recommend finding a local Subie specialist to work on it rather than many other general mechanics.
Hell yes. I tried the low range on my Impreza just once and didnt see any point in it. The gear reduction isnt significant in any way useful. I've now driven in winter conditions for a few months and it's "awd" does what it should. Its a hawkeye and that has mechanical 4wd. The 2.0R is plenty for winter time unless you really need to be ken block which you dont really have to or can handle.
The AWD behaves differently on a lift. To localize wheel bearing noise I put my 2015 Subaru Forester 2.0 690 AWD on four jack stands and ran it in drive for a couple of minutes. As expected when wheel speed sensors detected imbalance I got a traction control warning. After that only the front wheels were turning. Then a minute later I got a flashing AT temp warning so I shut the test down. It made me wonder if the oil pump was driven by the rear wheel output shaft. Or, possibly the clutch was so loose it led to concern about overheating? Anybody have thoughts? I erased codes and it is back to normal on the street.
The oil pump is typically driven by the input shaft of automatic transmissions. CVT's use a multiplayer clutch pack so the computer must have released oil pressure to limit the overheating causing only the front wheels to spin.
As I demonstrated in this video, it is possible to have the rear wheels stationary while just the fronts rotate, that's how the "differential" part works.
G’day Sir! I salute you for your teardown explanation.. I am Into old Toyotas but man this is really interesting stuff and your explanation is crystal clear! Subaru’s awd is really an engineering marvel!
It should be noted that the Tailshaft Center-diff clutches are “wet clutches” meaning they are bathed in fluid. The hydraulic system is separate as it’s applying the pressure via piston and hydraulic fluid to clamp the clutch plates but by no means does that automatically denote the clutches as “wet” and bathed in oil. Many LSDs use friction plates with material; they tend to wear out faster which is why wet clutches are superior for longevity. I’m sure maximum torque transmission is probably sacrificed on some level but for your average daily driving consumer, that would not matter. Read Wiki’s description of Nissan’s Atessa E-TS and you will see that the hydraulic fluid for clutch engagement is in fact separate from the transfer-case fluid that bathes the clutch pack plates; they explicitly state this in the description. In fact in this case two separate grades of fluids are also used. It should be said that hydraulic actuation for wet clutch plates is usually done as a design choice to simplify the system into everything operating off the same fluid though so E-TS is kind of an anomaly. Though my all time favorite center diff traction aid is VC (viscous couplings), electronically controlled wet clutch packs are the best compromise in every area in my opinion. Electromagnetic actuated clutch packs are another alternative but I believe have higher failure rates and are more complex. Not to mention the amount of R&D that’s gone into wet clutches as they are in most automatic transmissions; they are perfected systems.
I had Legacy between 2002-2015 270K km with not a sinlge issue except a radiator upper plastic tube died after 220K . It was 2.0L 125hp 4AT AWD car, a pure please to drive...
the 4wd clutch is all that drives the rear wheels,not a "centre differential" which was used on manual boxes,the standard 4wd clutch is very weak and non turbo engines bust them,cos they dont cut in until front wheels are already spinning,and it is set to come in softly ensuring some gnarly slip if your fullthrottling it and the front wheels are spinning,it then disintergrates and puts shrapnel all thru gearbox,jamming valves in valve body,selecting 2 gears at once and grenading whole gearbox,already done 1 box in my subaru 1990 liberty that way and the 1997 liberty gearbox i put in has started to go the same way,they need more clutch plates possibly solid brass faced and computer and valve body reprogramming to make them cut in hard
@@speedkar99 look carefully at the parts,its not a centre differential,its just a gear coupling,as a qualified mechanic and subaru owner i can without doubt say the rear wheels in automatic 1990 onwards subarus are only driven thru a clutch,it doesnt suffer from axle wind up because it releases or slips,i do have a snow switch in centre console which holds car in 2nd gear with 4wd clutch locked in
Worth to mention that in the selеctor position 1 the central dif remains locked on the low speed. In the past quite often the fail of the solenoid C caused the fail of RWD part, so Subaru became FWD only. We even installed a switch to toggle between FWD and AWD back in the days :)
The overall layout is virtually the same as Audi. Well, the longitudinal powertrain Audis. Subaru and Audi are the only two companies that use this layout on a regular basis. BTW, they are also alike in CVTs: they are the only two companies that make CVTs with a chain (waaay more durable than the conventional belts). Damn, this transmission is sooo clean and kinda new inside!
I used to work for subaru and I will say I was surprised when I found out all Subarus (except the BRZ and solterra) have different awd systems same with diffs
Excellent video with very clear explanation of what is happening inside the mystery box. I own a 95 Legacy automatic, and have owned several others of similar and earlier vintage. DO those cars used a similar setup or do they have the more simple viscous coupler?
Thank you so much for this! You make amazing content! I just bought a 2023 Crosstrek with a manual transmission. Could you maybe speak on some of the differences between the auto and manual. I plan to service my car for its lifetime and there aren’t many places to get details on it, without taking it apart myself. Thank you!
Try googling the service manual for your car. There’s great communities out there that provide service manuals that Subaru techs use. But I don’t know if they’ll have the newest ones.
Hi there, how does this compare to the Haldex AWD system ? I believe the only major difference would be that the clutch pack is at the rear diff instead of the front ? Then what are the "unique" advantages of Subaru's AWD ?
AMAZING! I guess the Forester isn`t very different. And make me think that I should change the cheap synthetic "supermarked" oil I filled last summer with original OEM oil. Because to be honest it doesn`t change that smooth anymore...
For 300km that trans is in pretty damn good condition. But yeah you should also do a tear down of the cvt. Subarus have some pretty solid ones and I’d love to see a rip down of one.
I'd love to see one too!
It sucks to think that cvts are usually weaker than a standard geared transmission.
@@vipervidsgamingplus5723 i mean logically speaking, one can clearly see how a belt driven pulley is weaker than gear on gear and clutches
Seems to be a good CVT Transmission, my dad has a 2019 Outback.
Except the very homosexual „fake shifting“ its very good
@@shakalpb1164 yeah thats one thing i dislike with all companies that are using cvt’s. The fake shift mimicking. Just let it be a cvt, everyone already knows it is so let it hold the high revs and push power
I've been into Subarus for 20+ years, and this is the best teardown of a Subaru transmission I've ever seen. Would love to see an STI transmission, or at least the front diff.
Glad you enjoyed it
I agree on the front differential teardown and rebuilt too with setting up the backlash!
An incredible piece of engineering! Kudos to you for your understanding of how it works & your excellent explanation
Thanks. It took me a few days but I studied it a bit and tried to understand it. I love appreciating these wonders of manufacturing and engineering.
I love you too
@@speedkar99 how did you study it?
@@18890426 Other youtube videos.
It’s amazing the amount of engineering that must go into designing transmissions like these! Just the tear down with all those clutches makes my head spin!
The base design is by nissan. Alot of the parts interchange into the older nissan pathfinder transmission.
I agree. Manufacturing and engineering! Then everything gets taken for granted.
I am mechanicly inclined ,and let me tell you ,my head was spining to,and it gave me a dose of modesty.
Watching this begs the question: Who thought this all up and made it work? Fascinating. Thank you.
I'm sure the engineers started with something much simpler and then just kept adding onto it.
@speedkar99 same as computers. Those are on the different level of complexity, but you can still understand the basic architecture and how stuff works.
Mr Subaru.
Vw
@@vihreelinja4743people be hating on mr Subaru because he likes snap on and Subarus, I think he’s cool
Meanwhile in an alternative universe a dentist is giving a lecture with a wrench.
😂🔧
@@SouthMainAuto That was pretty clever😁
Lol! I was about to comment that but I believe you it exists.
Came for the info, stayed for the insane sound of the impact wrench edited together quickly.
Glad you enjoyed it. It's very tedious to edit
I love your videos! Are you working on a Subaru one? 👀
Soon enough! @@nairb2
Aging Wheels has some great impact/drill edits too.
Subaru AT VTD system is pretty ingenious. I recall when I owned my Impreza I could feel torque shifting between the front and rear axle when I was driving on a snowy frozen lake. Cool stuff.
That's cool! From what I understand the torque split isn't that different between the front and rear wheels, probably 40/60. Interesting that you could even feel that much.
@@speedkar99It's actually 45F/55R. Just like in a WRX. That's actually a Torsen center diff.
You should try Acuras SH-AWD, that system really transfers power between the wheels.
got big balls eh to drive on a frozen lake
@@BMW_Z4idiot thanks sir! Got an old video on my channel of it
From someone who’s driven Subarus all their life and now drives a Mitsubishi Triton for Work , let me tell you I have taken Subarus traction and control on the road, especially in wet weather for granted!!!!! These new two wheel drives, front wheel drive or rear wheel drive, on a hill slight bit of rain, and you just slide everywhere. Subarus control is unprecedented, taking into account the small increase in fuel consumption, and lack of being able to switch between two wheel and four wheel. They’re amazing
Nice
How would you guys know? This video is about the most uncommon. by far, Subaru AWD, the VTD. Variable Torque Distribution -- the most premium AWD system that Subaru ever made, and not cheap. You don't get this expensive piece of kit in a Crosstrek, Forester or Legacy. Ha ha. Dream on if you think so. Relatively, very few VTDs were made, fitted mostly to Legacy GT and H6 models until 2016 -- but only with the automatic. One version that worked with manual transmission was fitted to all STIs and Legacy Spec B cars with the real heavy duty 6-speed manual transmission -- you'll never find that tranny in a mere WRX.
The manual transmission many choose in a WRX has a regular gear centre differential, with an all but totally useless viscous limited slip can of wonder-juice hooked between front and rear axle outputs. Its torque rating is only about 30 lb-ft or 40 nt-m. And that only happens when there's hundreds of rpm difference between the shafts to front and rear axle, and the special fluid actually then heats up enough to lock up the plates to transmit a reative drip of torque. Like, when does that happen? Almost never. Viscous limited slip is just about useless in practice. In cars. And many rubberneckers, no doubt including many viewers, think a viscous unit is a differential! How uninformed can people be? Completely, I'd guess. The unit is there for JDM specmnship and does not do much at all. And, by the way, AMC had the Eagle for 1978, and it had a gear centre differential with a viscous limited slip with a better torque rating than Subaru ever had 15 years later. The unit was made for AMC by Chrysler's New Process Gear Division. So VW/Audi were handily beaten to quattro by Detroit. Roy Lunn led the AMC design team -- google him and learn something. Nobody here knows their historical stuff, it's obvious.
Most Subaru AWD systems are the cheapo MPT system. Multi-Plate clutch, first came out for the '88 model year. Compared to a Haldex, the only difference was that, instead of disconnecting the MPT clutch entirely from the drive to the rear axle when not needed, Subaru chose to make a guess and allow springs to give about 10% torque to the rear wheels at all times, so the clutch never fully disengaged. And "Symmetrical AWD" was born in the marketing man's mind. It's hooey. Subaru upped that initial force to 40% of some theoretical number for the '99 model year. All pure guesswork. Because, simply, the tires make the axles turn at the same speed anyway, so the clutch almost NEVER has to slip much and overheat -- '90s Subarus centre clutches rusted solid together, and you had to do a violent reverse 90 degree J-turn to unstick the plates! Saw the chief mechanic doing that many times at my Audi/Siubaru dealer. Mrs Smith would come in complaining about juddering when she parked and had to do tight turns. Well, rust acted just like my first quattro's centre diff lock, and made those automatic MPT Subies full time 4WD. It's how this more typical Subaru MPT AWD and that updated Torsen C system in later Audis get by with such a drippy, not very strong clutch -- hardly ever has to actually DO anything, like slip much and generate heat.
I'm a retired mechanical engineer. I have owned an original '86 Audi quattro, an '88 Subaru GL Turbo with the first MPT AWD system, a '90 Eagle Talon AWD turbo, a '94 Audi 90 manual with Torsen centre diff, a '99 Impreza with MPT, and an '08 Legacy GT with the exact transmission and AWD system you tear apart here in this video.
My considered opinion, after having watched a few of your videos is that you do a very poor job of explaining anything. You talk too fast like carny barkers, skip over most everything, and seem clueless. To me, at any rate. Nobody could learn anything from this once-over-lightly nonsense of a non-explanation, far as I can tell. And the comments reflect that, frankly. The viewers haven't learnt a thing either. Maybe you think you know what's going on, but I'd bet you don't most of the time. Unless you are mechanical savants, and not just guys with a machine-gun delivery style and full of blarney and gift of the gab.
In my opinion, of the six AWD cars I've owned, the best in awkward conditions was the '94 90 Quattro, followed by the Subaru VTD in the Legacy GT. Then the Talon, then the original quattro in diff-lock mode. The Subaru MPTs were obviously FWD by comparison, and their drive to the front wheels is permanent anyway. The '94 90 Quattro was an understeering pig of a car with a very lazy V6 engine that could hardly pull the skin off a rice pudding. Overall, I did not like it except in sbow and on ice.
So, to me, when you say Subaru symmetrical AWD explained in the video title, and then you pick Subaru's most sophisticated and expensive AWD system, and NEVER mention that it's hardly typical of the average Subie, thus giving your average plodder of a viewer entirely the incorrect impression of what resides in their Crosstrek chariot, yo have done them a big disservice. Argue your way out of what I know to be true if you can.
I am NOT impressed,. Because this video isn't close to explaining anything to anyone, in my considered opinion.
@@BillMalcolm-tn3kq do you always come off as a pompous prick?
Subaru engineering on their drivetrain system is top of line. What their cars are capable of is simply incredible. Another well made Japanese based product
Agreed. Quite the feat here
Just wish they put the same effort into their motors :(
You probably didn't own a SVX 😅
Yeah sure…that EJ sure had a lot of thought put into maximizing reliability and durability…NOT!
Garbaggio, hot steamy piles of it. Literally. 😊
@@brandonsmith3447 Plenty of NA EJs kicking around with high mileage. Especially early 90s dual port EJ18s and 22s.
Seen a few EJ251s and early non-avls 253s with over 400k on them.
Are they Toyota RZ (4cyl out of early Tacomas/T100s) reliable, no, but far from the worst things you could buy.
A lot of thought went into the engineering and design of this transmission. A lot. Makes me appreciate the amount of planning and execution to make all this happen in one unit. Integrating the front differential with the transmission makes perfect sense and saves space too.
The next time I see a Subaru on the road. I will go out of my way to smile and wave at the owner because quite frankly they absolutely deserve it.
Thanks
Dang, great video explaining this complicated Subaru AWD Engine; what a beauty, so that's why they're so good on rough terrain, and durable and expensive
It sure is a touch setup. I like it
@@speedkar99 Really Well designed, the only that I don't like, is the price, but I guess it's worth it. This is for Wagons/SUVs right, not cars/hatchbacks?
@@saultube44Afaik they suvs are just lifted crossover wagon versions of their sedans?
@@angelolagussa1312 AFAUK, until you know, your speculations are of no relevance to me
@@saultube44dunno if it’s exactly the same but all Subarus have this AWD system.
Just came here because I was getting torque converter codes on my '13 Crosstrek and wanted to understand the whole transmission system better before I took it in. Thanks so much for your breakdown and explanation. This video was amazingly helpful to get a little education and I feel I will definitely be to better understand what the service mechanic tells me about the issue I'm having.
You are welcome. Hope you solve the issue.
incredible how intricately these engines are designed.
I hope you gonna lay your hands on subaru Lineatronic CVT some time in the future. Its almost 14 yrs old now and should hit junkyards soon.
I wish it was that easy. Even if they were there at this age, junkyard transmissions are like $300 after core plus I gotta pull it.
You Sir, are magnificent, And your videos are about as in-depth as it possibly gets.
thank you soo much for giving me the knowledge of the automotive world.
You are welcome! The best way to learn is to take something apart.
Thank you for this explanation of the basic automatic transmission. You made it very easy to understand. Best of RUclips 100%
You are welcome!
Amazing, how engineering mind comes to these ideas/designs, then even more amazing is how the production is quickly designed to make the parts in volumes from the drawings to the tooling and most amazing is how in a few years a completely new model gearboxes are out and all starts almost from the scratch. But one thing I am sure is you can never put it back together again (11:41).
Very nice presentation (as always) and showing how we take things for granted. When the average person buys the car, get the keys and starts the engine the last thing on his/her mind is the complexity of parts that allows us to drive it the way it is designed for.
Your videos will always change the way we look at the car machinery after watching them. There is an old Chinese proverb from 500 BC (maybe philosopher Confucius?): “I hear I forget, I see I remember, I do I understand.” Well your videos are the bridge between see and do. Not only we see it but almost like as we did it ourselves. But not only that, many times you through into your videos some facts from statistics or experiences you will not find in manuals especially when you talk about good or bad things in design or manufacturing.
So thanks for doing these videos and sharing with everyone. I hope you get enough financial support to continue doing what you are doing but even more for your wife and brother. I hope they will never run out of money for their new clothes and underwear. And toothbrush.
Well said! I agree 100%
I am very thankful for your feedback. I'm glad that people can benefit, just as I do when I learn as I tear things down. I didn't learn any of this in engineering school.
Seriously complicated technology and your knowledge is amazing too. Keep up the streams, I really look forward to them. Cheers from UK..
Thanks. I'm sure it started alot simpler and they just kept adding onto it.
12:15 I don’t think those are “sun” gears with “step-down planet gears” around the input and output shafts, that you might see with a ring gear. To me those look like they are functioning as differential side gears, going around together with both shafts until there is a difference in speed. Which is also why there are so many!!
5EAT with the VTD system. It's actually a WRX AWD system with no adjustment. That clutch pack in the rear by the *Torsen* center diff is actually to alter the torque split from 45F/55R to about 50/50. Even if it wears out completely, you still have 45F/55R.
Yes it's 45/55.
however, I don't understand how this is a torsen differential I don't see any worm gears
The 2015+ WRX CVT uses this style center diff, not the 5spd nor split case WRX 6spd manual. The VTD center diff is actually a Planetary Gear differential. A Torsen would apply friction to limit slip. The VTD clutch pack limits the slip.
I like how you respond to every comment. ❤
Love from South Denver Subaru Club
Thanks. I try to at least
This video is fantastic! Thanks man! Nice pace, no awkward pauses or silent streaks, very well explained and very entertaining.
Glad you enjoyed it!
Very interesting, it sounds like that when the AWD clutch is engaged, this system operates more like 4WD than AWD.
Yes but Most 4WD uses low gear range
That valve body thing looks a-maze-ing inside!
It sure is amusing!
When you look at the complexity it's amazing any of it works at all.
You are the best teacher and no equal to you.
Thanks
That particular planetary centre diff (on the 5EAT) has a 40/60 F/R split when the clutch is open.
Isn't it 45/55? 2005 Outback
@@speedkar99 Could be me misremembering! Just knew it wasn't a 50/50.
You are expert in your clear and perfect explanation of the planetary gears, hydraulic and solenoid works. Thank you.
Just so you know: an open diff is a constant 50/50 torque split. People often confuse that. An lsd or in this case the clutch pack allows the torque to go to the wheels that have the most traction.
Therefore, when the diff is locked, it’s not a 50/50 split but a xx/xx split, meaning it changes dynamically. If both front tires are on ice and both rear are on asphalt, 90 something percent of the torque will go to the rear with the diff locked.
I understand your point. I sometimes get confused between torque and RPM.
Also this diff is technically 45/55 seeing the difference in the size of the sun gears driving the output shafts.
@@speedkar99 yes but when its locked, that ratio goes out the window a bit depending on where traction is available
The STI drivetrain is very strong and it’s a stock trans and all that. I’m throwing over 600 ft lbs at it and it’s holding well.
Nice!
Pumped for the Subaru content! Let's GOOOOOO!
No problem. I got an H6 Engine teardown and a differential video from this Outback coming soon.
Great video! Awesome to see the inside of the valve body. First time seeing the combination planetary gearset + clutch for me. I am more familiar with the 4EAT which IIRC are full-time FWD with a clutch pack that can send some power to the rear (or fully lock like a transfer case).
It sure was interesting to dive in and see how it works! This is such old technology but I can learn alot.
There really isn't much difference between the 4EAT and 5EAT VTD system other than the added planetary gearset for the rear bias.
@@niuhuskieguy True! But with a VTD gearset, the car can never enter a 'FWD-only' mode, correct?
@@avsti Correct. If the clutch packs aren't active, the system will be like a basic all time 4x4 with centre diff. Much closer to the manual transmissions than the 4EAT.
Just stumbled upon this video , absolutely fascinating ! I don’t even own a Subaru and I rewatched it twice 😂
Thanks..glad you appreciate and can learn something new!
I guess its time you own one. -from a new Subie owner.
The trick to cutting with a cordless grinder is to use the thinnest cutoff wheel you can find. 1/16” or 1/32” works well. But no matter what they are power hungry.
Yeah that's why I'm sticking with the corded grinder. The cordless one is for filing my toe nails 🤣
I’ve owned Subaru outback for years I think they’re the best car ever thank you for this video not that I am that capable but I often wondered how it all worked with the gearbox thank you very much indeed you’re a clever man😊
You are welcome. I learn by taking things apart just like this.
As it says in a Haynes manual, reassembly is the reverse of the disassembly procedure 👍🏻🇬🇧
With some persuasion yes
The valve body is (literally) an analog mechanical computer.
Yep! Except it's electronically controlled with solenoids.
Controlled by a (literaly) digital computer. @@speedkar99
I have a 2001 Outback LL Bean with the H6 engine. My understanding is that the transmission logic is as follows:
* In first and second gear, the differential clutch is actuated hydraulically and there is a 50/50 torque split. Always.
* In third and fourth gear, the computer releases the clutch such that 90% of the torque goes to the front axle and about 10% goes to the rear, simply to reduce drag/increase fuel mileage.
* In third and fourth, the system monitors front and rear axle speeds, and if the front axle spins faster than the rear, then the clutch is progressively engaged until speeds are equalized. It can operate the opposite way to reduce rear axle speed as well.
* Both axles use limited slip differentials to control side to side wheel speeds.
The VDC cars work totally differently, and have no limited slip differentials, they use torque vectoring in order to provide stability control and the center differential is totally different. They can also give 50/50 torque splits in higher gears. This system is similar to the system in the STI's.
At least that is my understanding....YMMV.
Thanks for your input, it makes sense at higher gears and thus higher speeds, the front wheels are mostly powered, similar to other crossover type vehicles
Thanks for your effort . Mrs has a 2012 Outback 3.6r with that trans . I am a retired auto tech but did most of my work on Fords . I you pull the plug on the pan you get 4 qts out of it . I have been changing just 4 qts every 20000 miles . Trying to make the car go as far as possible . Those clutch packs look good for the mileage that unit had .
Yep it sure looks clean.
Keep doing fluid changes and it should last a while
I find the variety of differential and transfer case types to be extremely interesting.
Plated diffs with electromechanical control, or electrohidraulic, or electromagnetic, or gerotor pump, geared lsd's, center diffs for transverse engines, torque vectoring diffs with or without spider gears and planetary gearsets
This VTD subaru is one of their finest, at first it was viscous, later it switched to electro hydraulic.
Lexus GS has a similar system before 2007, with planetary open diff with plates, after 2007 they switched to a torsen C fully mechanical diff
Not often you see a Subaru 5EAT taken apart. I wished they ran a 4.111FD instead. I also wished Subaru put the VTD center diff as standar across the model line up. It's a much better AWD system. Your average non-car person wouldn't know the difference between the multiplate transfer clutch VS this VTD center diff. Awesome video!
Thanks. These don't fail too much that's why they aren't apart
I am a bit technical. But not even close enough to fully understand how all this system of levers, gears, clutches... works. Still, I drive a Forester. So thank you so much for the video!
You are welcome
Great vid!
If I ever have the misfortune to use the wealth of information, I'll def come back!
The best itip I got out of this was the extended socket to avoid the mess when removing the oil drain plug.
Thank you!
You are welcome
I can easily follow along & understand how an ice engine works & what all the parts are doing. I understand how a clutch & fluid torque converter work. The fluid torque converter itself is pretty genius. In how how they were able to use fluid & centrifugal force. To move the weight of an entire car with no actual mechanical shaft connection from the engine to the transmission drive shaft. But when in it comes to transmissions with all the gears, parts, valves,etc.. It boggles my mind trying to folliw along & fully grasp how all those parts work together & exactly what's going on inside.
I understand where you come from, it's because it's hard to visualize gearsets moving and clutches activating.
@@speedkar99 Plus trying to visualize how all the fluid travels around in the worm tray & trying to visualize what's happening in the valve body....I think the fluid changes directions and travels in different paths in the worm tray depending upon what gear it's in & how fast different shafts are spinning.
But it's still mind boggling & I don't understand how someone can fully grasp everything that's going on inside......🆚 something like a jet turbine that's pretty easy to fully grasp how it all works.
Incredible video and explanation, had 6 Subarus manual and autos now. Love my 5spd AT behind the flat 6, incredible engineering. If you have a Subaru I highly recommend finding a local Subie specialist to work on it rather than many other general mechanics.
They seem easy enough to work on by anyone, except all these rusty fasteners.
Loved it! Thanks for going to all that trouble. Hope it pays off for you.
You are welcome! I hope so, as long as people learn something new!
my subaru has a manual transmission, its very fun in the snow
Awesome
Thank you for taking the time & making a video full of knowledge for everyone curious out there :)
Love your videos of pulling these things apart! If you ever get your hands on a subaru dual-range 5 speed manual, I'd love to see a vid on that!
Hell yes. I tried the low range on my Impreza just once and didnt see any point in it. The gear reduction isnt significant in any way useful. I've now driven in winter conditions for a few months and it's "awd" does what it should. Its a hawkeye and that has mechanical 4wd. The 2.0R is plenty for winter time unless you really need to be ken block which you dont really have to or can handle.
That would be cool, I never knew they had low gearing.
Awesome teardown and explanation 👌
Thanks!
The AWD behaves differently on a lift. To localize wheel bearing noise I put my 2015 Subaru Forester 2.0 690 AWD on four jack stands and ran it in drive for a couple of minutes. As expected when wheel speed sensors detected imbalance I got a traction control warning. After that only the front wheels were turning. Then a minute later I got a flashing AT temp warning so I shut the test down. It made me wonder if the oil pump was driven by the rear wheel output shaft. Or, possibly the clutch was so loose it led to concern about overheating? Anybody have thoughts? I erased codes and it is back to normal on the street.
The oil pump is typically driven by the input shaft of automatic transmissions. CVT's use a multiplayer clutch pack so the computer must have released oil pressure to limit the overheating causing only the front wheels to spin.
As I demonstrated in this video, it is possible to have the rear wheels stationary while just the fronts rotate, that's how the "differential" part works.
G’day Sir! I salute you for your teardown explanation.. I am
Into old Toyotas but man this is really interesting stuff and your explanation is crystal clear! Subaru’s awd is really an engineering marvel!
It should be noted that the Tailshaft Center-diff clutches are “wet clutches” meaning they are bathed in fluid.
The hydraulic system is separate as it’s applying the pressure via piston and hydraulic fluid to clamp the clutch plates but by no means does that automatically denote the clutches as “wet” and bathed in oil. Many LSDs use friction plates with material; they tend to wear out faster which is why wet clutches are superior for longevity. I’m sure maximum torque transmission is probably sacrificed on some level but for your average daily driving consumer, that would not matter. Read Wiki’s description of Nissan’s Atessa E-TS and you will see that the hydraulic fluid for clutch engagement is in fact separate from the transfer-case fluid that bathes the clutch pack plates; they explicitly state this in the description. In fact in this case two separate grades of fluids are also used.
It should be said that hydraulic actuation for wet clutch plates is usually done as a design choice to simplify the system into everything operating off the same fluid though so E-TS is kind of an anomaly.
Though my all time favorite center diff traction aid is VC (viscous couplings), electronically controlled wet clutch packs are the best compromise in every area in my opinion. Electromagnetic actuated clutch packs are another alternative but I believe have higher failure rates and are more complex. Not to mention the amount of R&D that’s gone into wet clutches as they are in most automatic transmissions; they are perfected systems.
Thanks. Yes that is a wet clutch. They use them in automatic transmissions and they do last long.
Amazing how complicated that system is. We definitely don't think about that when buying a car
Agreed! So many parts to make it work.
Thank you for making this! I have been looking for a demonstration of these things for the longest time ever!
You are welcome
So cool to actually see all the parts. I love it!
Me too
Que paso guey.
Another extremely thorough and easy to digest video.
Big fan bro. 💪🏼
Appreciate it!
I had Legacy between 2002-2015 270K km with not a sinlge issue except a radiator upper plastic tube died after 220K .
It was 2.0L 125hp 4AT AWD car, a pure please to drive...
They sure can be reliable cars once the headgaskets have been taken care of.
Thank you for the teardown. I was wondering what do you do with all the guts after the video? Are they scrap? Or do you put it all together again?
Scrap!
Actually in STI models you have adjustable center diff and i believe it go up to 70% back to 50/50
_Now to get it back together ready for a 7am start tomorrow!_
the 4wd clutch is all that drives the rear wheels,not a "centre differential" which was used on manual boxes,the standard 4wd clutch is very weak and non turbo engines bust them,cos they dont cut in until front wheels are already spinning,and it is set to come in softly ensuring some gnarly slip if your fullthrottling it and the front wheels are spinning,it then disintergrates and puts shrapnel all thru gearbox,jamming valves in valve body,selecting 2 gears at once and grenading whole gearbox,already done 1 box in my subaru 1990 liberty that way and the 1997 liberty gearbox i put in has started to go the same way,they need more clutch plates possibly solid brass faced and computer and valve body reprogramming to make them cut in hard
The system you are describing are more typical of FWD based crossover vehicles.
Subaru's don't decouple the rear wheels.
@@speedkar99 look carefully at the parts,its not a centre differential,its just a gear coupling,as a qualified mechanic and subaru owner i can without doubt say the rear wheels in automatic 1990 onwards subarus are only driven thru a clutch,it doesnt suffer from axle wind up because it releases or slips,i do have a snow switch in centre console which holds car in 2nd gear with 4wd clutch locked in
Thank you for the video. Can you install 5EAT instead of a 4EAT? Is that even possible?
Impressive description throughout the tear down. You have a gift for teaching!
Glad you could learn something new! Thanks
5:09
That's what I like to hear, thanks man!
Haha
Worth to mention that in the selеctor position 1 the central dif remains locked on the low speed. In the past quite often the fail of the solenoid C caused the fail of RWD part, so Subaru became FWD only. We even installed a switch to toggle between FWD and AWD back in the days :)
Awesome! My brother installed a toggle on his Infiniti G37
This guy is brilliant.
Thanks !
You are welcome
so, when the display says 'check transmission'... what would you do? :)
Check the transmission to see if it's still there 😶
Transmissions are crazy sophisticated to me....let alone AWD systems.
Wow, you are incredibly fast !
You're an excellent teacher !
Thanks
The overall layout is virtually the same as Audi. Well, the longitudinal powertrain Audis. Subaru and Audi are the only two companies that use this layout on a regular basis.
BTW, they are also alike in CVTs: they are the only two companies that make CVTs with a chain (waaay more durable than the conventional belts).
Damn, this transmission is sooo clean and kinda new inside!
I'd love to teardown an Audi transmission and a CVT Subaru some day. This one is 300km and still sparkly clean.
That is very interesting info. No wonder Audi and Subaru have very good 4wd/awd systems.
Amazing engineering. Thanks for this video and your explanation. Now I must clean up the wall behind me from everything that went WAY over my head. 🤣😂
I'm glad you learned something, as I did too!
Great 👍 info. Does the WRX have a separate reservoir for the center differential apart from the front differential and transmission?
Awesome video! Can you put it all back together???😅
did he just say ez clap, didnt know you were chill like that
Yeah boy! I'm not that professional around the home lol
Thank you for making this video!
You are welcome
Can you do a video on E-CCVT? Electronic controlled variable valve timing for intake
Great vid, clutches & steels, bands wrap around drums and carriers
This one had no bands and drums
Excellent explanation!
Thanks
I used to work for subaru and I will say I was surprised when I found out all Subarus (except the BRZ and solterra) have different awd systems same with diffs
Yeah they certainly are different
Good to know. 70 retired diyer drive a 98 honda prelude and a 2006 subaru sti
Nice!
Excellent video with very clear explanation of what is happening inside the mystery box. I own a 95 Legacy automatic, and have owned several others of similar and earlier vintage. DO those cars used a similar setup or do they have the more simple viscous coupler?
Likely an open center differential
Thank you so much for this! You make amazing content! I just bought a 2023 Crosstrek with a manual transmission. Could you maybe speak on some of the differences between the auto and manual. I plan to service my car for its lifetime and there aren’t many places to get details on it, without taking it apart myself.
Thank you!
Try googling the service manual for your car. There’s great communities out there that provide service manuals that Subaru techs use. But I don’t know if they’ll have the newest ones.
@@NATA5II I have tried. Most of the stuff is pretty vague, or for the last model type. I’m considering purchasing an AllData subscription for the car.
All data can help.
I'm sure the Crosstrek is somewhat similar, except it doesn't have a lockup clutch and just an open center differential
Hi there, how does this compare to the Haldex AWD system ? I believe the only major difference would be that the clutch pack is at the rear diff instead of the front ? Then what are the "unique" advantages of Subaru's AWD ?
That IS a nice, thick, beefy shaft!
😋
Will you be posting the re-assembly video?
Definitely superior manufacturing! Well done Subaru…..other brands start taking notes
It sure is solid
Interesting concept. Thanks for sharing...
You are welcome.
AMAZING! I guess the Forester isn`t very different. And make me think that I should change the cheap synthetic "supermarked" oil I filled last summer with original OEM oil. Because to be honest it doesn`t change that smooth anymore...
As always,LOVE this video Brotha!!! Along with your detailed explanation and showings of everything!!! Great video!!! : >)
Thanks!!
please do a subaru cvt. great video
I sure will...if I can find one.
1:39 i thought it was funny how you quickly ended your sentence to note how cool it looks. i feel the same way lol
Do all Outbacks and Legacies have a limited slip rear differential?
And where's the video on that.
Pff, the engineering that went into this. Thanks for tear down.
You are welcome!
Excelente!!
That it's made by JATCO?
I'm not sure. Didn't see any stampings on the housing.
That double seal is wild, do they ever have problems with gear oil and ATF mixing together?
I wonder if they do!
I also don't see why they couldn't have used the same fluid seeing that other FWD cars share the same ATF.
@speedkar99 yeah my 94 camry auto has separate drain/fill plugs for the transmission and the differential, but they both take Dexron III
hope the baby and fam is well!
Thanks for remembering! We are doing well.
It's cold out so the baby won't make an appearance anytime soon.
Happy holidays homey @@speedkar99
AMAIZING video!!, thank you so much.
You are so welcome!
How about a CVT teardown Very interesting and simply explained
Yes I'd love to get a Subaru CVT one day. I already have videos of other CVT teardowns if you want to check it out.