Build a bear *differential*

[x X Cloud X x]

Just hit 80k while taking the family on a weekend trip of course the loud whining noise starts to happen 😭 just when I decide to take it out for the first time since July 4th. drove it straight into the shop to see if it was a wheel bearing or dreaded rear diff. my bestie after getting it up on a lift tells me welcome to the club. I need a new diff. 🥹

Going to order one through Diffsonline since they are local to me in MA. but before I place an order figured minus well ask my fellow M brothers on what is needed and what isn’t.

Looking into staying with a stock rebuild 3.62 gear
-M Variable
-No on REM Ring & Pinion Polishing
-No on REM Diff Bearing Polishing
-Add diff mounts = Stock OE Front
-No on magnetic drain plug
-Need fluid was thinking of Castrol SAF-XJ FM 75W140
1fill 1.5L for $204

ps - feel free to mock this build up or if u guys approve this car is mainly for spirited weekend drives with the family

[EthanolTurbo]

M variable is garbage and constantly needs to be rebuilt FYI.

[discoelk]

Don't bother with a stock rebuild. Just get a used one off CL or FB marketplace.

[ugaexploder]

curious, but is there is a reason why you are not opting for the polishing?

[sapote]

curious, but is there is a reason why you are not opting for the polishing?

My guess it costs $$ and it's not needed.

"No on REM Ring & Pinion Polishing
-No on REM Diff Bearing Polishing"

What is exact bearing polishing?

[sapote]

I need a new diff. 🥹

I'm interested of what caused the whining noise. Unless the input shaft bearings are so bad the chance of pinion/ring whining is low. I think it could be just a bearing went bad and no reason to trash the diff instead of replacing the bearing.

[ugaexploder]

My guess it costs $$ and it's not needed.

"No on REM Ring & Pinion Polishing
-No on REM Diff Bearing Polishing"

What is exact bearing polishing?

I've wondered myself, or if there is any benefit to doing it. Probably just one of those things they can do for an extra charge and it gives people the fuzzies.

[sapote]

I've wondered myself, or if there is any benefit to doing it. Probably just one of those things they can do for an extra charge and it gives people the fuzzies.

I understand pinion/ring polishing, but what the heck with bearing polishing? The balls are already shiny and round.

[Slideways]

Which clutch pack is Diffsonline using? A few people said that the Racing Diffs clutch pack might not last as long as the OE clutch pack.

Another option is Wavetrac.

[0-60motorsports]

Which clutch pack is Diffsonline using? A few people said that the Racing Diffs clutch pack might not last as long as the OE clutch pack.

Another option is Wavetrac.

Yes OP get the wavetrac!

[Sharocks]

As someone who has a Diffsonline diff in their car (I know Dan well), for what you're asking for, just get an OE diff from a part out and save yourself the money.

[bigjae46]

REM polishing really isn't worth it unless you're trying to get every bit of performance. The only reason I do it is I have a guy that can do it for about 1/3 the price that most charge.

https://youtube.com/shorts/ad427nJpeNk?feature=share

I've had good experiences with the V1 racing diffs kit. Not so good with the V2 diffs. But I'd check the breakaway torque first, its probably still adequate for street use. If it's whining then it's very likely bearing related. As long as the diff oil is still relatively clean - some sparkles ok, no chunks - then its just a matter of replacing the races and bearings. Which is a couple hundred dollars. Takes 2-4 hours with the diff out of the car.

[x X Cloud X x]

Yes its currently making a loud whining noise kind of sounds like a wind up toy but it still drives excellent.... had the AKG rear diff bushings put in 2 months ago along with fresh factory fluids in rear diff... keep the comments coming appreciate it and its reassuring to see the different options I can go with

[ChapterM3]

Yes its currently making a loud whining noise kind of sounds like a wind up toy but it still drives excellent.... had the AKG rear diff bushings put in 2 months ago along with fresh factory fluids in rear diff... keep the comments coming appreciate it and its reassuring to see the different options I can go with

And you never experienced the whine until now? As soon as I put in ECS bushings I could hear everything, always wished I just stuck with OEM bushings, unless the thing is a track car I never go anything other than OEM, had to learn the hard way with those bushings

[s54brendan]

I've wondered myself, or if there is any benefit to doing it. Probably just one of those things they can do for an extra charge and it gives people the fuzzies.

That's exactly what it is haha

In terms of the R&P, why remove the hard coating you paid good money for that came directly from the factory?

In terms of bearings, imo it's simply foolish to do so