Diff rebuild - available options

[sapote]

know that Gizmo said there should be some free play in the right output shaft but id be surprised if the amount i have is considered acceptable. It certainly isnt to me, and based on what info i have found, at least the racingdiffs parts aim to fix that issue. Im not a mechanical engineer, so i dont know exactly what they were thinking but after 24 years in aviation thats a lot of forward/aft movement for a rotating part and i suspect it cant be helping

All Diff output flanges have that much plays, including open Diff. So don’t be surprised.

As advised, RacingDiff concave shim is not a good solution as it causes other things to wear faster. If you want less plays then add flat shims.

[Kcalhoun27]

[QUOTE=sapote;n262363]

Noisy when shifting and a bit when turning. Im also doing the wheel bearings because ill have the rear end torn apart, but from all the reading ive done, im confident the diff is the main culprit for the noise

/QUOTE]
Seeing the front mounting bolt is necked, this caused great noise.

Would just replace the output seals, o-rings, new clutch stack, reduce the side gears plays with flat shims.
But measure the total thickness of new clutch stack excluding any spring plates, and compare with the old stack first before installing

The stretched bolt is from the rear cover, its definitely not right, but it wasnt the cause of the noise. Im just glad it didnt break off in the housing, that would have been an absolute nightmare

i know that Gizmo said there should be some free play in the right output shaft but id be surprised if the amount i have is considered acceptable. It certainly isnt to me, and based on what info i have found, at least the racingdiffs parts aim to fix that issue. Im not a mechanical engineer, so i dont know exactly what they were thinking but after 24 years in aviation thats a lot of forward/aft movement for a rotating part and i suspect it cant be helping

that said, i dont think ill have a good answer until the new parts are installed.

i checked the other hardware, the front diff bolt looks healthy and the rear bolts are the new versions, replaced 3 years ago with ~1000 miles on them, although i will be replacing the hardware just in case

[sapote]

[QUOTE=Kcalhoun27;n261961]Noisy when shifting and a bit when turning. Im also doing the wheel bearings because ill have the rear end torn apart, but from all the reading ive done, im confident the diff is the main culprit for the noise

/QUOTE]
Seeing the front mounting bolt is necked, this caused great noise.

Would just replace the output seals, o-rings, new clutch stack, reduce the side gears plays with flat shims.
But measure the total thickness of new clutch stack excluding any spring plates, and compare with the old stack first before installing

[oceansize]

Diffsonline, like everything else, has gone up a bunch. My 3.91 in 2020 was 2500 (not including core charge) and is now 3200. This is one of those items I didn't want to fool with and didn't want to do twice (or more). Been very happy with Dan's work.

[bigjae46]

I'd just do the Diffsonline M-variable. The highest chance of doing it right vs trusting a shop that may or may not know what they are doing.

$2k is pretty good. I charge locals $1200 P&L if they provide a core.

[Kcalhoun27]

There are different models available. The most basic one starts at $1800ish. That + $900ish for labor, bearings, seals etc means your cost would be about $2700-2800. Not a bad price and it'll last way longer than the stock M variable that wears out quickly.

Where are you seeing these units for that price? A quick google has €2300 and up, nothing near $1800. I suppose stricly speaking that is still the similar price point as the wavetrac, so i appreciate the suggestion.

[EthanolTurbo]

From everything ive read about them, they are way above the use case for me. Also more expensive for no particular gain, as the stock diff is fine with me

There are different models available. The most basic one starts at $1800ish. That + $900ish for labor, bearings, seals etc means your cost would be about $2700-2800. Not a bad price and it'll last way longer than the stock M variable that wears out quickly.

[Kcalhoun27]

Another option you didn't list is a Drexler and having it built at a local diff shop.

From everything ive read about them, they are way above the use case for me. Also more expensive for no particular gain, as the stock diff is fine with me

[EthanolTurbo]

Another option you didn't list is a Drexler and having it built at a local diff shop.

[Kcalhoun27]

That is by design on v1 unit of how the lsd sits in the case, that the passenger side has shorter output shaft and has play, that is not the root of your can noises.

I have a few videos comparing and explaining v1 vs v2 diffs, could prove useful to watch.


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I watched your video (about the lsd rebuild, i had not watched parts 1 and 2 until today. Explains not seeing the v1 vs v2 difference)yesterday, i guess i missed the part where it shook around in the housing. That definitely seemed like it was not good, even if by design, but i will take your word on it

in either case, its clearly leaking and im guessing based on the grime everywhere on the underside of the car, its coming from the side seals. Weird that it wasnt leaving spots on the garage floor, im guessing that it leaks when driving.

If it isnt clear by now, im still learning on this part. Ive pulled this car apart before but i never really dug into the diff, beyond changing the fluid. But i know i put 1.7 liters into it and didnt get that out when i drained it. And the diff has not be refreshed before so it needs to be done.

i actually decided to buy the racingdiffs parts based on your video and it seeming like its a DIY as long as i go slow. Worked for the vanos, should work here as well

[mrgizmo04]

The right side stub has a good bit of play in it, so i think i can safely say that its the root of the

That is by design on v1 unit of how the lsd sits in the case, that the passenger side has shorter output shaft and has play, that is not the root of your can noises.

I have a few videos comparing and explaining v1 vs v2 diffs, could prove useful to watch.


Sent from my SM-S911U1 using Tapatalk

[Norocehcap]

I have the m variable from diffsonline, I put it in last month and have done about 2k miles so far so good. The car is going to Limerock next weekend, if I have any problems I'll update here.

[Kcalhoun27]

Pulled the diff and started disassembling in general, also to add some more context through photos. I do not know which version i have but hopefully this clears it up. The right side stub has a good bit of play in it, so i think i can safely say that its the root of the

[mrgizmo04]

V1 or V2? Always provide month/year build of the car in question.

You can't go by that if you are not the original owner of the car and don't know the history. Plenty of guys rip their diffs to crap early in the cars's life and replace entire diffs. Clutches start being noisy in less than 50k miles. Where they source them, who knows, junkyards, partouts, friends, Dan at diffsonline, etc. Then they strip the front bolt hole and get another diff.

While more likely that pre 2005 are v1, I wouldn't guarantee it without doing some more investigation, which halfshaft play, open rear cover, etc.

I have 4 diffs, most of them didn't meet the pre/post 2005 split expectation based on cars they came out of.

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[Kcalhoun27]

You have V1 Diff.
Sounds like the LSD clutch stack jerky slip and causes the M-clunk and noise during a turn, not bearings or ring/pinion issue.

Thats what i figured as well, but the noise is remeniscent of a failing wheel bearing and at 150k miles, its easy enough to do

that aside, is there any reason to choose one of the 3 listed options first? Other than price, i really dont have any recent reviews or info to base a decision off of, hence this thread. Ive read good and bad reviews of racingdiffs, majortiy good reviews of diffsonline, and a way too in depth description of why a wavetrac will show some wear after 300k miles, which im not sure is a worthwhile metric