Is nobody else going to comment about the body wrapped in the tarp in the bed of the truck? Lol maybe it is the engineer who designed the first gear set.
The report (in my mind ) is pointing out that the tooth engagement is "cutting" or "scrapping" the oil off of the surfaces.....not that it's squeezing it away. The too small clearance means the tip of the tooth, and only the tip, contacts first.....initial contact has a low surface area and hence high pressure load which "cuts or scrapes" through the oil. Edit to add: it's fantastic to see these things investigated further, this is where true understanding happens. Thanks to all.
When I slapped in 4:56 gears in my bronco, I didn't really understand how important break in procedure is. Started towing cars to my local race track immediately after I got it together. The next morning I noticed the noise about 10 minutes in omw to the track, by the time I got there, it ate all the teeth on the ring gear and coasted into the pits. So now I'm here on erics videos learning about my fuck up. As usual hahaha. Thank you for all the vids throughout the years man.
I was just watching an older ETCG video (the OBD comparisons with Paul Danner) when this new vid popped up. You wouldn't know they have six years between them. We've always had the best quality and advice with Eric's productions - still the best on RUclips. Long live ETCG!
Absolutely great way to conclude the hunt for the noise... Even though the exact cause for the noise is up for discussion, I think there even more value to be had in understanding the multiple caused that could be at play... The devil is in the details... I think this will give any of us with less experience then you a great head start if we're going to try a differential rebuild...
over my 40+ differential gear set up has been my biggest problem, but I did not have a lot of experience in this area as my specialty is electronics diagnostics, but I worked briefly with a guy in a mom and pop shop, that could take a gm of ford differential, slap in the gears, do his thing, and everyone of the damn things worked perfectly evetime. he was my go to guy for this. Just shows what experience can do. I never seen him use more than regular hand tools, impacts and a dial indicator gauge. he just had that talent.
I’ve done engines before. I finally did my gear, and remember all the work it took to get your Fairmont gear right, so I knew that it was no “walk in the park” , but I had pulled the carrier out at least 10 times writing down which shims were used and back last measurements. I’d go back to a set of shims in the same order, and get a different measurement. It WAS a lot of work! Finally got it darn close, and checked the pattern, and it was about as close as you could get it to match the pattern s in the instructions, and a book that I bought about rears. I haven’t done a lot of miles on it, but so far so good!
One key piece of understanding is that is does not take much "out of spec" to cause gear noise. I ran into this on an LT1 Caprice. I thought just replacing the pinion bearings and seal would take care of it. Set of 3.42 gears took the rest of the noise out of it.
Great video, 3 years later!! Going through & cleaning out old email, I found this series wondered how it ended up, great research!! My only experience has been pinion bearings about 40-45 years ago, first one on a '67 Dart when I broke my dad's breaker bar getting the nut off, second a '65 IHC heavy half ton pickup. On the pickup, the pumpkin came off, I had the bearings pressed off & on at a shop, it had a solid spacer that I borrowed a micrometer from work to set up. That truck had rust spots on the gears, but I left them & it worked ok, never heard noise after the bearing replacement.
Hey Eric. I do a lot of diff rebuilds here in the U.K. And I learn more and more every time you post a new video. Thanks for the great work and information
As a DIY what I took away from this is if I need a rear-end setup, this is where I stop and pay somebody to do it. :) But I am not running a youtube channel to teach people automotive repair. There is a point as a DIY, that I know a professional is needed.
Majorly helpful video. I just did the rear end in my 2016 Ram 2500 and have run into the exact same noise. Trying to figure out the noise, whether it was the gears or bearings, was a joke. The people I would have expected to know had no idea or felt the bearings were to blame, even though I felt it sounded like gears feeding on each other. That said I am now putting another gear set in the rear and having a shop do the job start to finish this time around.
You are one super mechanic Eric....you do us a great enormous favor when you show & explain to your viewers all that you go thru when repairing & analysing a mechanical problem in the Workings of any automobile. I’m just a backyard mechanic...family & friends & my own vehicles, sometimes I run across situations where I’m beating my head against the fender...can’t figure out why it’s not coming out right ! You have taught me to stop-think-analyze. Frankie in Massachusetts
Thanks, been following through the whole process. I Have a 93 Silverado that looks just like yours but an extra cab. Did the motor, Monster trans replacement and have all my parts for a ring and pinon swap. (posi unit too). Been a mechanic for 30 plus years and still a bit gun shy about doing this job. Even sourced a buddy with the pinon depth tool. Your videos have helped light the fire to do it. thanks again...
Thankfully I never had to mess with a dif. But all the detail that goes into it, and the fact I don't have the equipment, is why I hope I never have to!
I've only had to do one gear swap which was adding a spool to a Toyota Pickup rear. Though the video is on my channel, I realize after your conquest that it wasn't optimal for highway use. So far years later no issues or noises have arose. Moving forward, I'll reference your videos for accurate information for future videos and projects. Thanks to Robert for donating his time and effort for the viewers sake. Yet again, thanks Eric for your time in the editing of the filming
@@ETCG1 ERIC......DONT BEAT YOURSELF UP! MY ANALYSIS IS......YOU SUFFERED FROM A CASE OF FRIDAY GEARS! THOSE GEARS WERE MACHINED BY JIMBO! WITH A SIX PACK AND A SPECIAL SOMEONE ON HIS MIND....LETS CALL HER LOLA(ford reference there) and I'd still ship my 59 Cadillac to you
That failure analysis was great! Amazing what they can find out there. When I did my Ox Locker install, I reused the ring and pinion, since the truck only had 97k on it, and everything looked good there. The carrier, side, and spider gears were another story - those were all super worn, with the tips of the side gears knocked right off for who knows what reason (more than likely, cheapery by GM). Backlash was WAY off on mine. Before the install, it was .011" - spec was .004"-.006"!! As luck would have it, it was .004" - .0045" after installing the new carrier and bearings. I get an extremely faint howl only under certain conditions, like very light throttle, but only at a certain speed range. Nobody can hear it but me. Silent accelerating, and silent coasting. Pattern was good. I attribute that to wear that must've been caused by the carrier being out of whack for so long.
I have a 1997 F-350, I’ve had a OX LOCKER AIN the front D60 for years, buy one last year for the rear and it needed a rebuild. Piñon bearing was seized, cost me a lot more than I was expecting, however I have new ring and pinion, bearings, ujoints, and axle orings. I didn’t notice the noise when it was wore out. When the gears were setup it was quiet, and way way less drivetrain loss. Anyway I love the OX lockers, I tell everyone that want the ARB to try out a OX, nothing but a push cable is fantastic l.
@@JAMESWUERTELE - Yeah, they're great units. I have the air-actuated setup. Cables don't last up here in the rust belt, otherwise that would've been my 1st choice. I already had the compressors, since I used to haul cars all over the Northeast and occasionally to FL, so it was a no-brainer. Didn't cost me any extra at the time.
Setting up diffs can be extremely tricky. I had the diff in my e46 set up by a shop In Costa Mesa because I just wasn’t confident in doing it myself. Love the videos
Oh Eric, thanks for the cake! I have been watching your channel for 7 years and learned so much useful knowledge about cars before college. You helped me a lot to get into the trade. Heck, I should buy you a cake someday!...
I rebuilt a ford 8.8 for my ranger 4 years ago. It has made almost the same noise as yours from day one. I’ve never had it back apart to try to find the issue. It now has almost 50,000 miles on that gear set.
Even if you went in and adjusted gear contact at this point the noise would likely still be there as the gears have 'worn in'. If you can live with the noise, keep going. Thanks for the comment.
Hey Eric, just wanted to thank you for the very thorough series of diff rebuild videos you did on this truck. I just refinished rebuilding my first differential, on my own dad's truck,. and your sharing of knowledge has been invaluable. I only hope I managed to get everything close enough to perfect!
You, and people like you, are the reason I made these videos in the first place. Thank you very much for taking the time to comment. I hope your differential turns out great! Thanks for the comment.
Awesome video as usual. Just finished rebuilding a differential with new gears and like you struggled between shim thickness steps. Backlash was either 0.05mm or 0.11mm with spec being 0.06-0.10mm (I’m in the land of Aus so metric down under). I settled for tighter given the new gears will naturally wear-in.
Great video, having a similar problem myself with a chrystler 9.25 rear end, just installed aftermarket 3.91 gears and they whine when decelerating, a little bit when accelerating as well. Backlash was set correct and pinion depth looks good, may have to take a closer look at my wear pattern though. When I pulled the gear cover to check the wear pattern there was only a very small amount of debris in the oil after about 150 miles, hopefully no damage was done, the noise is only barely noticeable anyway
Hi Eric setting up diffs is an art on its own. From my own experience setting up. I go in steps before I pull down the unit. My first thing I would get a torque wrench and see how much pre load on the bearings and check specs ect on the pinion. Next be gears for runout with a dti. Also shims ect. I've found for me oil is a safety barrier. That's why they call it Xtreme pressure. Personally when setting up backlash you have to have a mindset about that my gears are doing. I setup alot if diffs for many years and I believe when you get a understanding of the simple mind you can do it with your eyes shut. When I was a a young apperitce I did five diffs under a hour all hypold diffs I found are easy to set up then the Chevy 10 bolt.
The concept of point contact (the sharp leading edge of the gear) piercing the oil film is fascinating. The subject area is called "tribology" in general. ✌😁
It is easy to get "simple" things wrong when you have to use sacrificial parts for setup that may not be absolutely identical to your permanent parts including wear/crush from assembly-disassembly cycles and have to take everything apart every time you want to change one shim.
Threadlock on the spider gear pin pinch/lock bolt is a must, if that bolt loosens and comes out while you are going 70 on the interstate, you are going to have a bad time...Don't ask me how I know.
I am going through this right now. I’ve set up my new gears three times now, and they still make noise! It’s a 8.6 in a 2000 Silverado. I’ve ordered a pinion depth tool to see what’s going on. I really think the pinion is wrong. It looks like it’s contacting right on the edge like yours was. I may grab a different gear set and see what happens. I am a master tech for Mercedes and have never had this much trouble with anything! Gear purgatory….
Could it be the gear tooth helix angle, on the pinion, and ring, are cut at two slightly different at angles from the factory? It doesn't take much to throw the system out sync. From a machinist.
I'm having the same issue with the same gm 8.5 rear end. I installed a set of 3.42 gears with a limited slip differential. All new bearings were used and I admit I used the pattern to determine pinion depth. Like yours (Eric), the pattern looked great. I drove the car for a 2 years (summer only driving) and when I drove the car this year (summer 2020) I suddenly had a noise developing that seems to have gotten worse as time went on. The backlash was about .006. I thought maybe the carrier bearings were too loose because the noise would change going around bends in the road. So I added .003 to the shim pack and of course my backlash changed to .009, which is still within spec. Didn't help. In fact, it started making some very loud noises recently which is prompting me to take some action. I am now ready to tear the whole thing apart and reinstall my 2.73 open diff (bearings, shims and all) to see if the noise is gone, I expect it will be gone. I have not seen any indication of something gone wrong but after I remove the LSD and 3.42 gear set this time, I will take a very close look at the wear pattern. I just am not ready to spend the money on new gears etc. and the pinion depth tool. I am considering the Ratech pinion tool for the GM 8.5 since it is very affordable. Maybe try a new setup with new gears over the winter. Any comments or help would be appreciated. Love your videos and have learned a good deal from you! Keep it up!
Would the difference in wearing locations from throttle and coast have to do with pinion angle changes when throttle is applied or not applied (coasting)?
Shearing the oils away from the work surface Will cause premature wear on the metal similar to low EP oil (extreme pressure) breakdown And hydrodynamic wedge. Also, the pinion leading edges do not have the proper edge prep, hone or radius. That 0.004" you were off makes a huge difference if it's already on the edge of the depth requirements.
Eric, great videos as always. Just put a rebuilt LSD diff in and after 20mins of quiet driving, it starts to clunk. I have only driven 70miles at no speed more than 40mph, plus no hard acceleration. Any pointers please?
Just a random comment; the object in the trunk resembles a miniature wrapped "body bag" with the "head" part resting on the wooden plank. Hehe 😁 Just sayin'. P.S.: Oh and give me likes as I was the first one to comment about this - I shouldve written a time stamp; stupid me.
I have only changed the gear oil in a differential. That's my limit as a DIY'er. Interesting stuff here Eric, but I could not help myself getting side-tracked on the object in the back of the Truck. My guess it's something for the Integra? And if I'm wrong we will see it anyway in a future ETCG1 video.
I had a similar problem, Gear tooth pattern seemed to look good, backlash was like .004 or .005, within spec, pinion bearing preloaded correctly ( i had previously incorrectly reused the crushsleeve after crushing it to much because i managed to get the same amount of preload), and I get a faint howl on decel, it was way louder before i fixed the preload. Idk if I ruined the gears having done the preload improperly the first time but nothing looked crazy or broken and I had roughly 100miles on it before i fixed the issue. Also when its up in the air in drive in idle, it sounds like a bearing rubbing on something. When I took it apart the first time I noticed the inner bearing on the pinion was scored, havent taken it apart since the crush sleeve fix. I might have around 500 to 1k miles on it and it still makes weird noises but whats weird is I can hear a sound on acceleration when I'm near walls too. Im wondering if I didnt put enough shims inbetween the carrier bearings and the housing.
I don't know Eric it looks like the pinon was too far in leveling the gears to mesh towards the outer side of the ring gear so I'll call too much torque on the pinion crush sleeve let me know what you think about my conclusion
Pinion rotational torque was bang on so I don't think that had anything to do with it. Also, pinion sleeve crush has nothing to do with pinion depth. That's controlled by the shim under the pinion bearing. BTW my pinion depth was only .002 out of spec. Thanks for the comment.
@@ETCG1 ok but the wear pattern show it was to far forward good contact would be middle of the the ring gear so it make sense that it to far forward in the case the other possibilities would be the wrong gear set any man
I’m in no way a expert but from my research and finings. The gear tooth pattern run is the final say in correct setup. Assuming you have proper piñon preload , side bearing preload, and backlash. I think as “precision” as the pinion deapth tool is, it’s used to get you close. If both patterns on coast and drive are not centered then adjustment is needed.
@Kris Nicholson yeah, I try to avoid Differential and Transmission stuff when I can. I mostly just don't wanna lol. But pretty much anything else I have.
I want to know how you put the camera under the truck without it falling down or getting damaged? I want to locate the source of a noise on my Tahoe. Thanks.
I have one that is bad noises and I have pulled it 7 times and reset and it is still making a lot of noise and I have rebuilt hundreds over the years and I have never had one do thisCK
I'm a machinist. You want to talk differentials I gave up and started making my own damn shims. The stuff on the store shelf sucks and I have yet to find one that's actually accurate to my measurements.
Thanks for the info Eric. I've been having a hard time getting the right pattern with a gear set I recently purchased, it has a similar pattern as the one you had issues with but its brand new out of the box... Or is it? Regardless, I'm going to make the most of it, run it and replace it with something that's hopefully better in the future. The set was from USA Standard Gear.
i got hella noise on cost and slight noise on drive at about 55 mph then it goes away until i cost again, i can do 80 mph on the highway and hear no noise, 2008 crown vic 218,000 miles, guess i might be replacing the diff sooner or later
well... I still can't belive I changed the ring gear section (keept the chims at thier place) and had no problem at al for 6 years and it goes strong today. 180km/h many, many times to.... yeah. just spalled it in by 10 minutes and got going again...
I've installed 2 ring and pinion sets on 2 different trucks. The first one made noise immediately, and the second started making noise after about 200 miles. I. Both cases it was my fault because I had my pinion preload way out of spec.
Maybe the manufacturer had the wrong depth put on that gear? So even though you were pretty bang on, they had determined the incorrect depth for you to adjust to. No clue, but I like the analysis!
I'm currently setting up a new Ford 8.8, and my tooth pattern is too close to the toe on the drive side, and too close to the heel on the coast side. I've made several changes to pinion depth and backlash, but the pattern never seems to get closer to center. This is frustrating and I'm running out of ideas.
I have 250 miles on my new gears that i installed.. there is a whinn at light accel between 55-60 .. hard accel --no noise . decell no noise .above 65 no noiose... what do you think i should do ? which way should i move the pinion? in or out? sh it this sucks because i have to take the whole thing apart agian. 2013 taco. im sure you know the feelings
Hey Eric I had my gears set up at a known shop and it was incorrect. I went and re did it after they told me nothing was wrong, howls at cruise. I haven’t gotten a proper answer for my question. If it was set up incorrect and driven is the gear set trashed after that? Still have a howl at cruising speed it get louder as it gets warmer.
i have a similiar wear pattern in a jeep dana 44 rear.ive never messed with them but gear wear is covering whole side of both sides of ring gear.ive not heard any noises but its harder to hear anything but seems the whole hogs head gets a little hotter than the other axle that was previously in it.so im worried about premature failure and it has tru-lock diffs and i dont want to trash them out.any way i could send pics of gear wear and the mesh of rear ring gear and get your input.Thank you eric,your my favorite.please respond either way.i know your busy too,.thank you.
@@dosbox907 i have popped covers off and ran backlash checks.its all in spec.its rubicon dana 44,s front and rear.when i installed them i replaced all fluids.had some small metal flakes,expected cause it probably never changed and wear pattern just looked like it is covering almost entire tooth drive side and coast side and these jeep lockers have very tight fit.like 0006 .i have some pics and ive did tons of research and no noises or any heat problems but i know what pattern id prefer but it covers both sides from deep but not bottomed out in gear but more like near an 1/8 in. from bottom and same at top and toward inside of carrier and also toward outside of teeth.i would prefer it be not so tall and not quiet so wide.but i know it could be worse.any ideas.Run it till something happens? think ill run for while then re-check oil and look for metal again and re-check backlash and pattern.any ideas or comments appreciated
Great video Eric. I recently rebuild my '66 Falcon differential, (I learned a lot from your Fairmont videos btw) but unfurtunately it just exploded!!!... I think I nailed the gear tooth pattern, because it was amazing for months, but it looks like I forgot to install the spider gears shaft pin!!!. Seems to me that it slowly slid off its place until it contacted the pinion and suddenly all hell broke loose. :'(
I hope this isn't the case and that the new gears don't wear out, however, if they do...i suggest you take that case out, clean it spotless and either send it to be measured for squareness or do it yourself. In the swap video i saw those marks in the gear and after hearing the detailed report, and an expert eye's words on it, i'm pretty sure something is wrong with the casement itself. It might be one of those things that's barely noticeable, but gets worse with wear and use. There's the bonus of the fact that you won't be driving this truck as a truck would be driven, so, this change, if it happens, won't be noticeable any times soon, maybe never from now on.
Hard to say really. What I find interesting is that I'm out even further with the new gears concerning clearances yet they don't make any noise at all.
Did anyone take into account the oil thickness? The minute someone mentions oil "thickness"- all they think of is viscosity. I'm asking- how much room does the oil take up between surfaces? It all adds up.
I don't know the exact number, but if you watch the video linked in the description about how I solved the problem with new gears, there is a clip where I used synthetic fluid instead of regular fluid.
I'm not entirely convinced it was me either, but I have to assume some responsibility. If nothing else to let viewers know the perils of differential service. Thanks as always for your comment.
Most differential failures are caused by a bad metal on the bearing race since they don't use timken bearings and race and quality gears made in USA or Germany like in 1950 s
You could have saved $1000 Measure the carrier BRG bore with the cap bolted on and see if it's the same as the race diameter for reference.(Should be --0.0002) Using a PC of ground Starrett bar stock, subtract it's thickness from the measure down to the pinion. I've done it Many times and now I find myself @ 70 yrs old having to do it once again because the mechanic has failed Twice on my Z28 toy.
I just regeared my ford 8.8 and it whines on deceleration but I’m just going to leave it. I only drive like 3,000 miles a year and the truck has 170,000 miles. The ring and pinion will probably last the rest of the trucks life.
Perhaps NOW do an inspect on wear pattern and see what it looks like Now with all things are proper?? The report seems reasonably more close to real issue root cause! Oil cavitation - oil starve issue prevents sufficient lubrication Compounding improper clearances was enough to cause this. I also have always had to do Troubleshooting like this too in my job to locate ROOT causes on machine functionality of things and the wear pattern is always a point I focus on. The deduce the alignment -gaps specs and it always comes down to either alignment or Gap spec improperness causes the issues. Minimum oil will do a fairly good job up to severe torque compression overrides it This seems like the same “whining” that the M21 Rock crushers usually have in their gears due to the design & the Gear drive type timing sets have the same metal-metal whine noise. Except the Diff is under a lot more thrust would naturally make more noise. A “historical comparison” to other scenarios would be good to see what other same conditions were like.
The report didn't say anything about 'improper clearances'. Granted, my clearances were not exact, but they were not that far out of spec either, .002 with backlash and pinion depth. Funny enough, my new gears are .004 out of spec concerning pinion depth, and I'm also out .002 on backlash, yet they don't make any noise at all. Thanks for your comment.
@@ETCG1 I’d blame the material quality in part here and MFG specs or and on possible mismatch. You did your job close enough to be done “ properly” and here show another example, a little more Out of spec and all is OK, .
Is nobody else going to comment about the body wrapped in the tarp in the bed of the truck? Lol maybe it is the engineer who designed the first gear set.
Lmao, your comment made my day!
no no... that was my first thought.. why is there a midget body in the tarp behind you? nevermind the gear fail
I came to the comments just to see if someone had already say something about it and it was the first one😂😂
Yea Eric got em with a shovel! Ping!! Thump!
Mr. moog will be right next to him! Lol!
The report (in my mind ) is pointing out that the tooth engagement is "cutting" or "scrapping" the oil off of the surfaces.....not that it's squeezing it away.
The too small clearance means the tip of the tooth, and only the tip, contacts first.....initial contact has a low surface area and hence high pressure load which "cuts or scrapes" through the oil.
Edit to add: it's fantastic to see these things investigated further, this is where true understanding happens.
Thanks to all.
Just the tip
When I slapped in 4:56 gears in my bronco, I didn't really understand how important break in procedure is.
Started towing cars to my local race track immediately after I got it together.
The next morning I noticed the noise about 10 minutes in omw to the track, by the time I got there, it ate all the teeth on the ring gear and coasted into the pits.
So now I'm here on erics videos learning about my fuck up. As usual hahaha.
Thank you for all the vids throughout the years man.
I was just watching an older ETCG video (the OBD comparisons with Paul Danner) when this new vid popped up. You wouldn't know they have six years between them. We've always had the best quality and advice with Eric's productions - still the best on RUclips. Long live ETCG!
Thank you! Paul is a good friend and a great technician.
Gear geometry is critical. Anything howling is a definite indication something is wrong. Good job Eric
Absolutely great way to conclude the hunt for the noise... Even though the exact cause for the noise is up for discussion, I think there even more value to be had in understanding the multiple caused that could be at play... The devil is in the details... I think this will give any of us with less experience then you a great head start if we're going to try a differential rebuild...
That was the point. Thank you very much for your comment.
over my 40+ differential gear set up has been my biggest problem, but I did not have a lot of experience in this area as my specialty is electronics diagnostics, but I worked briefly with a guy in a mom and pop shop, that could take a gm of ford differential, slap in the gears, do his thing, and everyone of the damn things worked perfectly evetime. he was my go to guy for this. Just shows what experience can do. I never seen him use more than regular hand tools, impacts and a dial indicator gauge. he just had that talent.
I’ve done engines before. I finally did my gear, and remember all the work it took to get your Fairmont gear right, so I knew that it was no “walk in the park” , but I had pulled the carrier out at least 10 times writing down which shims were used and back last measurements. I’d go back to a set of shims in the same order, and get a different measurement. It WAS a lot of work! Finally got it darn close, and checked the pattern, and it was about as close as you could get it to match the pattern s in the instructions, and a book that I bought about rears. I haven’t done a lot of miles on it, but so far so good!
One key piece of understanding is that is does not take much "out of spec" to cause gear noise. I ran into this on an LT1 Caprice. I thought just replacing the pinion bearings and seal would take care of it.
Set of 3.42 gears took the rest of the noise out of it.
Great video, 3 years later!! Going through & cleaning out old email, I found this series wondered how it ended up, great research!! My only experience has been pinion bearings about 40-45 years ago, first one on a '67 Dart when I broke my dad's breaker bar getting the nut off, second a '65 IHC heavy half ton pickup. On the pickup, the pumpkin came off, I had the bearings pressed off & on at a shop, it had a solid spacer that I borrowed a micrometer from work to set up. That truck had rust spots on the gears, but I left them & it worked ok, never heard noise after the bearing replacement.
Hey Eric. I do a lot of diff rebuilds here in the U.K. And I learn more and more every time you post a new video. Thanks for the great work and information
Thank you!
As a DIY what I took away from this is if I need a rear-end setup, this is where I stop and pay somebody to do it. :) But I am not running a youtube channel to teach people automotive repair. There is a point as a DIY, that I know a professional is needed.
Majorly helpful video. I just did the rear end in my 2016 Ram 2500 and have run into the exact same noise. Trying to figure out the noise, whether it was the gears or bearings, was a joke. The people I would have expected to know had no idea or felt the bearings were to blame, even though I felt it sounded like gears feeding on each other.
That said I am now putting another gear set in the rear and having a shop do the job start to finish this time around.
You are one super mechanic Eric....you do us a great enormous favor when you show & explain to your viewers all that you go thru when repairing & analysing a mechanical problem in the Workings of any automobile.
I’m just a backyard mechanic...family & friends & my own vehicles, sometimes I run across situations where I’m beating my head against the fender...can’t figure out why it’s not coming out right ! You have taught me to stop-think-analyze. Frankie in Massachusetts
Thanks, been following through the whole process. I Have a 93 Silverado that looks just like yours but an extra cab. Did the motor, Monster trans replacement and have all my parts for a ring and pinon swap. (posi unit too). Been a mechanic for 30 plus years and still a bit gun shy about doing this job. Even sourced a buddy with the pinon depth tool. Your videos have helped light the fire to do it. thanks again...
Thankfully I never had to mess with a dif. But all the detail that goes into it, and the fact I don't have the equipment, is why I hope I never have to!
I've only had to do one gear swap which was adding a spool to a Toyota Pickup rear. Though the video is on my channel, I realize after your conquest that it wasn't optimal for highway use. So far years later no issues or noises have arose. Moving forward, I'll reference your videos for accurate information for future videos and projects.
Thanks to Robert for donating his time and effort for the viewers sake. Yet again, thanks Eric for your time in the editing of the filming
Thanks for the follow up. Glad to see you're doing more of these type of videos.
That dude that did the analysis is awesome! Sounds like the lack of oil between killed it by factions! Such a cool video Eric
I've learned so much from this channel, thanks again sir.
My goal is to educate. I very much appreciate your comment, thank you.
@@ETCG1 ERIC......DONT BEAT YOURSELF UP!
MY ANALYSIS IS......YOU SUFFERED FROM A CASE OF FRIDAY GEARS!
THOSE GEARS WERE MACHINED BY JIMBO!
WITH A SIX PACK AND A SPECIAL SOMEONE ON HIS MIND....LETS CALL HER LOLA(ford reference there)
and I'd still ship my 59 Cadillac to you
That failure analysis was great! Amazing what they can find out there.
When I did my Ox Locker install, I reused the ring and pinion, since the truck only had 97k on it, and everything looked good there. The carrier, side, and spider gears were another story - those were all super worn, with the tips of the side gears knocked right off for who knows what reason (more than likely, cheapery by GM). Backlash was WAY off on mine. Before the install, it was .011" - spec was .004"-.006"!! As luck would have it, it was .004" - .0045" after installing the new carrier and bearings. I get an extremely faint howl only under certain conditions, like very light throttle, but only at a certain speed range. Nobody can hear it but me. Silent accelerating, and silent coasting. Pattern was good. I attribute that to wear that must've been caused by the carrier being out of whack for so long.
I have a 1997 F-350, I’ve had a OX LOCKER AIN the front D60 for years, buy one last year for the rear and it needed a rebuild. Piñon bearing was seized, cost me a lot more than I was expecting, however I have new ring and pinion, bearings, ujoints, and axle orings. I didn’t notice the noise when it was wore out. When the gears were setup it was quiet, and way way less drivetrain loss. Anyway I love the OX lockers, I tell everyone that want the ARB to try out a OX, nothing but a push cable is fantastic l.
@@JAMESWUERTELE - Yeah, they're great units. I have the air-actuated setup. Cables don't last up here in the rust belt, otherwise that would've been my 1st choice. I already had the compressors, since I used to haul cars all over the Northeast and occasionally to FL, so it was a no-brainer. Didn't cost me any extra at the time.
Setting up diffs can be extremely tricky. I had the diff in my e46 set up by a shop In Costa Mesa because I just wasn’t confident in doing it myself. Love the videos
how much did that cost you?
@@inqwhyringmindz I paid the guy who built the diff 300 and it’s been close to 40k miles and the diff is still performing as expected
Oh Eric, thanks for the cake! I have been watching your channel for 7 years and learned so much useful knowledge about cars before college. You helped me a lot to get into the trade. Heck, I should buy you a cake someday!...
Happy Birthday, and thanks for the comment!
I rebuilt a ford 8.8 for my ranger 4 years ago. It has made almost the same noise as yours from day one. I’ve never had it back apart to try to find the issue. It now has almost 50,000 miles on that gear set.
Even if you went in and adjusted gear contact at this point the noise would likely still be there as the gears have 'worn in'. If you can live with the noise, keep going. Thanks for the comment.
Thank you Eric I always enjoy watching your videos I am from South Africa
Hello again South Africa! Thank you for your viewership and comments.
Hey Eric, just wanted to thank you for the very thorough series of diff rebuild videos you did on this truck. I just refinished rebuilding my first differential, on my own dad's truck,. and your sharing of knowledge has been invaluable. I only hope I managed to get everything close enough to perfect!
You, and people like you, are the reason I made these videos in the first place. Thank you very much for taking the time to comment. I hope your differential turns out great! Thanks for the comment.
Thanks for the birthday wish! It is my birthday today!!
Happy Birthday!
Awesome video as usual. Just finished rebuilding a differential with new gears and like you struggled between shim thickness steps. Backlash was either 0.05mm or 0.11mm with spec being 0.06-0.10mm (I’m in the land of Aus so metric down under). I settled for tighter given the new gears will naturally wear-in.
Thanks for sharing Eric👍
This series is a guide for many of us, when doing differential repairs (especially noise related)😉
Stay Safe👍
That was why I posted so much on my experiences with this differential. Thanks for noticing and for the comment.
Great video Eric and thanks for keeping us updated Artie ❤️
Great video, having a similar problem myself with a chrystler 9.25 rear end, just installed aftermarket 3.91 gears and they whine when decelerating, a little bit when accelerating as well. Backlash was set correct and pinion depth looks good, may have to take a closer look at my wear pattern though. When I pulled the gear cover to check the wear pattern there was only a very small amount of debris in the oil after about 150 miles, hopefully no damage was done, the noise is only barely noticeable anyway
The title of this video before the comma sounds like an EE lecture.
Indeed
Everything has already been said, so I'll add this: that Pikachu is top notch! Always enjoy the videos
Very good informative update Video on the gear set and problem Eric
Great analysis, thanks for the look under the hood.
Hi Eric setting up diffs is an art on its own. From my own experience setting up. I go in steps before I pull down the unit. My first thing I would get a torque wrench and see how much pre load on the bearings and check specs ect on the pinion. Next be gears for runout with a dti. Also shims ect. I've found for me oil is a safety barrier. That's why they call it Xtreme pressure. Personally when setting up backlash you have to have a mindset about that my gears are doing. I setup alot if diffs for many years and I believe when you get a understanding of the simple mind you can do it with your eyes shut. When I was a a young apperitce I did five diffs under a hour all hypold diffs I found are easy to set up then the Chevy 10 bolt.
The concept of point contact (the sharp leading edge of the gear) piercing the oil film is fascinating. The subject area is called "tribology" in general. ✌😁
Tooth wear pattern backlash and preload are all you have to know to rebuild a differential. And never use a used crush sleeve always a new one.
I only have FWD cars, so I'm just listening to add it to my library.
The highlight for me was the Pikachu poster ⚡🐁
I changed the fluid, seals, and axle bearings in my '94 GMC Jimmy and that's as far as I'll ever go. I'd like the thing to move after I'm done!
It is easy to get "simple" things wrong when you have to use sacrificial parts for setup that may not be absolutely identical to your permanent parts including wear/crush from assembly-disassembly cycles and have to take everything apart every time you want to change one shim.
So true.
Very nice analysis that he did
Cant thankyou enough for the hard work u put into ur work videos!
Threadlock on the spider gear pin pinch/lock bolt is a must, if that bolt loosens and comes out while you are going 70 on the interstate, you are going to have a bad time...Don't ask me how I know.
هذا صحيح ..اسٱل مجرب ولا تسٱل طبيب..gm 10 bolt
That guy does have a really cool job
Hey Jeff, how are things on the other side?
James Nasto
The wireless is great here!!!!
Jeffery Epstein With my internet service here, I must be in hell.
I am going through this right now. I’ve set up my new gears three times now, and they still make noise! It’s a 8.6 in a 2000 Silverado. I’ve ordered a pinion depth tool to see what’s going on. I really think the pinion is wrong. It looks like it’s contacting right on the edge like yours was. I may grab a different gear set and see what happens. I am a master tech for Mercedes and have never had this much trouble with anything! Gear purgatory….
My experience problems have always come up from the Pinon depth
Could it be the gear tooth helix angle, on the pinion, and ring, are cut at two slightly different at angles from the factory? It doesn't take much to throw the system out sync. From a machinist.
I chased my tail with gear whine in a ls1 firebird, the aftermarket gears all has a little whine to them compared to the oem ones.
The problem with those particular vehicles is the Torque arm transmits any gear noise to the interior cabin.
I just installed motive 3.73 in mine. wonder how it will sound once i take it out.
PIKA! PIKA! lol just Pikachu creeping in the background
I'm having the same issue with the same gm 8.5 rear end. I installed a set of 3.42 gears with a limited slip differential. All new bearings were used and I admit I used the pattern to determine pinion depth. Like yours (Eric), the pattern looked great. I drove the car for a 2 years (summer only driving) and when I drove the car this year (summer 2020) I suddenly had a noise developing that seems to have gotten worse as time went on. The backlash was about .006. I thought maybe the carrier bearings were too loose because the noise would change going around bends in the road. So I added .003 to the shim pack and of course my backlash changed to .009, which is still within spec. Didn't help. In fact, it started making some very loud noises recently which is prompting me to take some action. I am now ready to tear the whole thing apart and reinstall my 2.73 open diff (bearings, shims and all) to see if the noise is gone, I expect it will be gone. I have not seen any indication of something gone wrong but after I remove the LSD and 3.42 gear set this time, I will take a very close look at the wear pattern. I just am not ready to spend the money on new gears etc. and the pinion depth tool. I am considering the Ratech pinion tool for the GM 8.5 since it is very affordable. Maybe try a new setup with new gears over the winter. Any comments or help would be appreciated. Love your videos and have learned a good deal from you! Keep it up!
Would the difference in wearing locations from throttle and coast have to do with pinion angle changes when throttle is applied or not applied (coasting)?
why is there a body in the truck bed?
Shearing the oils away from the work surface Will cause premature wear on the metal similar to low EP oil (extreme pressure) breakdown And hydrodynamic wedge. Also, the pinion leading edges do not have the proper edge prep, hone or radius. That 0.004" you were off makes a huge difference if it's already on the edge of the depth requirements.
Eric, Would it be possible to post or attach a link to the gear failure analysis report from Robert Bethel? The engineer in me has to know...
Yes, but I don't feel the need. The only page missing from the report was the cover page, everything else was shown in the video.
Aus, Ford Falcon BF 900k original diff... just thicker oil from 100k. Job done.
Eric, great videos as always. Just put a rebuilt LSD diff in and after 20mins of quiet driving, it starts to clunk. I have only driven 70miles at no speed more than 40mph, plus no hard acceleration. Any pointers please?
Okay lesson learned I'll always borrow my friend's expensive tools, to set my backlash and pinion angle.😎😊👍👍
Just a random comment; the object in the trunk resembles a miniature wrapped "body bag" with the "head" part resting on the wooden plank. Hehe 😁 Just sayin'.
P.S.: Oh and give me likes as I was the first one to comment about this - I shouldve written a time stamp; stupid me.
I have only changed the gear oil in a differential. That's my limit as a DIY'er. Interesting stuff here Eric, but I could not help myself getting side-tracked on the object in the back of the Truck. My guess it's something for the Integra? And if I'm wrong we will see it anyway in a future ETCG1 video.
It's a lawn chair that I use at car shows.
@@ETCG1 Lol!
For most of us Getrag 226 equipped Challenger/Charger/300C and some Corvette guys...we know all about gear whine.
I had a similar problem, Gear tooth pattern seemed to look good, backlash was like .004 or .005, within spec, pinion bearing preloaded correctly ( i had previously incorrectly reused the crushsleeve after crushing it to much because i managed to get the same amount of preload), and I get a faint howl on decel, it was way louder before i fixed the preload. Idk if I ruined the gears having done the preload improperly the first time but nothing looked crazy or broken and I had roughly 100miles on it before i fixed the issue. Also when its up in the air in drive in idle, it sounds like a bearing rubbing on something. When I took it apart the first time I noticed the inner bearing on the pinion was scored, havent taken it apart since the crush sleeve fix. I might have around 500 to 1k miles on it and it still makes weird noises but whats weird is I can hear a sound on acceleration when I'm near walls too. Im wondering if I didnt put enough shims inbetween the carrier bearings and the housing.
I don't know Eric it looks like the pinon was too far in leveling the gears to mesh towards the outer side of the ring gear so I'll call too much torque on the pinion crush sleeve let me know what you think about my conclusion
Pinion rotational torque was bang on so I don't think that had anything to do with it. Also, pinion sleeve crush has nothing to do with pinion depth. That's controlled by the shim under the pinion bearing. BTW my pinion depth was only .002 out of spec. Thanks for the comment.
@@ETCG1 ok but the wear pattern show it was to far forward good contact would be middle of the the ring gear so it make sense that it to far forward in the case the other possibilities would be the wrong gear set any man
I’m in no way a expert but from my research and finings. The gear tooth pattern run is the final say in correct setup. Assuming you have proper piñon preload , side bearing preload, and backlash. I think as “precision” as the pinion deapth tool is, it’s used to get you close. If both patterns on coast and drive are not centered then adjustment is needed.
I have zero experience doing differentials as of yet. But I've been told it can be a bit of a pain lol.
@Kris Nicholson yeah, I try to avoid Differential and Transmission stuff when I can. I mostly just don't wanna lol. But pretty much anything else I have.
I love your channel and I subscribed
I want to know how you put the camera under the truck without it falling down or getting damaged? I want to locate the source of a noise on my Tahoe. Thanks.
Magnet. As for your noise. www.ericthecarguy.com/faq/diagnosing-noises-in-your-car
Good to know and lessons learned.
I have one that is bad noises and I have pulled it 7 times and reset and it is still making a lot of noise and I have rebuilt hundreds over the years and I have never had one do thisCK
I'm a machinist. You want to talk differentials I gave up and started making my own damn shims. The stuff on the store shelf sucks and I have yet to find one that's actually accurate to my measurements.
I have to agree with you on that. It almost feels like they put shims in differential kits just to make the buyer feel better.
@@ETCG1 Pretty much
Thanks for the info Eric. I've been having a hard time getting the right pattern with a gear set I recently purchased, it has a similar pattern as the one you had issues with but its brand new out of the box... Or is it? Regardless, I'm going to make the most of it, run it and replace it with something that's hopefully better in the future. The set was from USA Standard Gear.
Some of us can tell a bearing groan from a ring gear and pinion whine. For you old deaf effers there is always a chassis ear!
i got hella noise on cost and slight noise on drive at about 55 mph then it goes away until i cost again, i can do 80 mph on the highway and hear no noise, 2008 crown vic 218,000 miles, guess i might be replacing the diff sooner or later
i love your videos
Thank you!
ETCG1 your welcome
well... I still can't belive I changed the ring gear section (keept the chims at thier place) and had no problem at al for 6 years and it goes strong today. 180km/h many, many times to.... yeah. just spalled it in by 10 minutes and got going again...
I've installed 2 ring and pinion sets on 2 different trucks. The first one made noise immediately, and the second started making noise after about 200 miles. I. Both cases it was my fault because I had my pinion preload way out of spec.
Maybe the manufacturer had the wrong depth put on that gear? So even though you were pretty bang on, they had determined the incorrect depth for you to adjust to. No clue, but I like the analysis!
I had that thought too, but I have no idea how to verify it.
As long as you are moving in the same direction backlash won't matter.
I'm currently setting up a new Ford 8.8, and my tooth pattern is too close to the toe on the drive side, and too close to the heel on the coast side. I've made several changes to pinion depth and backlash, but the pattern never seems to get closer to center. This is frustrating and I'm running out of ideas.
I've been there man. Sometimes you just have to commit and see what happens. ruclips.net/video/npUBF9Wj1Iw/видео.html
You need to increase your backlash tto 10 and see what happens usually on face hobbed geaes the patter will come together
I have 250 miles on my new gears that i installed.. there is a whinn at light accel between 55-60 .. hard accel --no noise . decell no noise .above 65 no noiose... what do you think i should do ? which way should i move the pinion? in or out? sh it this sucks because i have to take the whole thing apart agian. 2013 taco. im sure you know the feelings
Hey Eric I had my gears set up at a known shop and it was incorrect. I went and re did it after they told me nothing was wrong, howls at cruise. I haven’t gotten a proper answer for my question. If it was set up incorrect and driven is the gear set trashed after that? Still have a howl at cruising speed it get louder as it gets warmer.
Yes it is. Once a bad wear pattern is ingrained in the gears it's there for good unfortunately.
ETCG1 thanks, kinda thought so
Hole shots are a major contributor of noisey rear gears! Lol!
i have a similiar wear pattern in a jeep dana 44 rear.ive never messed with them but gear wear is covering whole side of both sides of ring gear.ive not heard any noises but its harder to hear anything but seems the whole hogs head gets a little hotter than the other axle that was previously in it.so im worried about premature failure and it has tru-lock diffs and i dont want to trash them out.any way i could send pics of gear wear and the mesh of rear ring gear and get your input.Thank you eric,your my favorite.please respond either way.i know your busy too,.thank you.
It might just be bearing failure.
Dont know till you pop the cover have a look.
Maybe you got mud instead of diff fluid rn
@@dosbox907 i have popped covers off and ran backlash checks.its all in spec.its rubicon dana 44,s front and rear.when i installed them i replaced all fluids.had some small metal flakes,expected cause it probably never changed and wear pattern just looked like it is covering almost entire tooth drive side and coast side and these jeep lockers have very tight fit.like 0006 .i have some pics and ive did tons of research and no noises or any heat problems but i know what pattern id prefer but it covers both sides from deep but not bottomed out in gear but more like near an 1/8 in. from bottom and same at top and toward inside of carrier and also toward outside of teeth.i would prefer it be not so tall and not quiet so wide.but i know it could be worse.any ideas.Run it till something happens? think ill run for while then re-check oil and look for metal again and re-check backlash and pattern.any ideas or comments appreciated
Great video Eric. I recently rebuild my '66 Falcon differential, (I learned a lot from your Fairmont videos btw) but unfurtunately it just exploded!!!... I think I nailed the gear tooth pattern, because it was amazing for months, but it looks like I forgot to install the spider gears shaft pin!!!. Seems to me that it slowly slid off its place until it contacted the pinion and suddenly all hell broke loose. :'(
Well that's unfortunate. Sorry to hear about it. I hope you're able to find a new differential. Thanks for the comment.
I hope this isn't the case and that the new gears don't wear out, however, if they do...i suggest you take that case out, clean it spotless and either send it to be measured for squareness or do it yourself. In the swap video i saw those marks in the gear and after hearing the detailed report, and an expert eye's words on it, i'm pretty sure something is wrong with the casement itself. It might be one of those things that's barely noticeable, but gets worse with wear and use.
There's the bonus of the fact that you won't be driving this truck as a truck would be driven, so, this change, if it happens, won't be noticeable any times soon, maybe never from now on.
Hard to say really. What I find interesting is that I'm out even further with the new gears concerning clearances yet they don't make any noise at all.
Maybe it was mix and match? Once was in a self-service parts yard, and saw someone pulling just 1/2 a gear set.
Today is actually my birthday! 57 years ago today I came into the world.
Happy Birthday!
@@ETCG1 Thank you 👍
It seemed to me that you never had a good enough set of shims to choose from when setting the gear mesh pattern.....maybe a problem with the case?
I have a 1991. My diff makes a bang. Just got worse. At first it was a little now it bangs
Thanks. It is my birthday. The cake looks delicious.
Happy Birthday!
@@ETCG1 Thank you very much sir.
Did anyone take into account the oil thickness?
The minute someone mentions oil "thickness"-
all they think of is viscosity.
I'm asking- how much room does the oil take up between surfaces?
It all adds up.
I don't know the exact number, but if you watch the video linked in the description about how I solved the problem with new gears, there is a clip where I used synthetic fluid instead of regular fluid.
Mismatched gear set from factory?
Gears are suppose to be machined to be a matched set from what I understand. Also, some of my measurements were out of spec so it's hard to say.
ETCG1 funny how the sound did not change when you did the adjustments and new bearings you know how these after market stuff goes!!
I didn't do any adjustments the first time. I just changed the pinion bearings and re-torqued them.
Maybe a bad casting on those gears? Sometimes someone gets unlucky
I don't think the first set of gears were much cop anyway.
i can't see the noise being all your fault eric.
What matters is they are smoooooth now :-D
I'm not entirely convinced it was me either, but I have to assume some responsibility. If nothing else to let viewers know the perils of differential service. Thanks as always for your comment.
Most differential failures are caused by a bad metal on the bearing race since they don't use timken bearings and race and quality gears made in USA or Germany like in 1950 s
You could have saved $1000 Measure the carrier BRG bore with the cap bolted on and see if it's the same as the race diameter for reference.(Should be --0.0002) Using a PC of ground Starrett bar stock, subtract it's thickness from the measure down to the pinion. I've done it Many times and now I find myself @ 70 yrs old having to do it once again because the mechanic has failed Twice on my Z28 toy.
Have you looked into the possibility that the original specs were wrong? We are not perfect.
I considered the possibility but I have no idea how to verify that.
I just regeared my ford 8.8 and it whines on deceleration but I’m just going to leave it. I only drive like 3,000 miles a year and the truck has 170,000 miles. The ring and pinion will probably last the rest of the trucks life.
Pleas upload on August 6th so someone will wish me a happy birthday! 😁
Sorry, ETCG1 videos get posted on Mondays. That said, Happy Birthday a little early.
Perhaps NOW do an inspect on wear pattern and see what it looks like Now with all things are proper??
The report seems reasonably more close to real issue root cause!
Oil cavitation - oil starve issue prevents sufficient lubrication
Compounding improper clearances was enough to cause this.
I also have always had to do Troubleshooting like this too in my job to locate ROOT causes on machine functionality of things and the wear pattern is always a point I focus on. The deduce the alignment -gaps specs and it always comes down to either alignment or Gap spec improperness causes the issues.
Minimum oil will do a fairly good job up to severe torque compression overrides it
This seems like the same “whining” that the M21 Rock crushers usually have in their gears due to the design & the Gear drive type timing sets have the same metal-metal whine noise.
Except the Diff is under a lot more thrust would naturally make more noise.
A “historical comparison” to other scenarios would be good to see what other same conditions were like.
The report didn't say anything about 'improper clearances'. Granted, my clearances were not exact, but they were not that far out of spec either, .002 with backlash and pinion depth. Funny enough, my new gears are .004 out of spec concerning pinion depth, and I'm also out .002 on backlash, yet they don't make any noise at all. Thanks for your comment.
@@ETCG1
I’d blame the material quality in part here and MFG specs or and on possible mismatch.
You did your job close enough to be done “ properly” and here show another example, a little more Out of spec and all is OK, .