M3 Limited Slip Repair

[Bernman]

Originally posted by Fair
... Just need to find E36 Euro halfshafts and diff mount.... anyone got any leads on Euro E36 M3 parts?

WTB:
Euro E36 halfshafts
Euro E36 lower diff mount
E36 M3 rear hubs/uprights/brakes

contact: fair@vorshlag.com

Thanks,

Try a PM or an email to simmons

http://www.bimmerforums.com/forum/me...fo&userid=4193

He seems to have a Euro parts connection and has sold a bunch of them on this forum...

[Mark85]

lets see some upclose pics of the chips, id run some emril pad/cloth over it to smooth it out

ive seen emril pad used on crankshaft bearings because they were nicked while taking the pistons out...so it should be safe in the diff

[cosmosm3]

tombmwe30

Are you the real Tom Bleh? The one that competes nationally in DSP. If so. Welcome to the boards. Glad you found your way here.

Just kidding Tom.

Guys
Tom is very knowledgable and has alot of experience. Welcome to the boards and to the E36 community.

[Tommy R]

Well, I passed by the local BMW dealer the other day and picked up a torx bolt (yes, they had one in stock!) and ordered all new diff cover bolts to replace the ones that got chewed up and I'll replace the remaining ones, too. The new ones will all go in with red Loctite. I also ordered a new pinion crush sleeve since the current one had to be re-torqued. (The previous owner of the diff swapped them)

BTW, I took the one torx bolt to a local bolt specialty store and picked up a dozen equivalent hex headed bolts so I won't have to deal with these stupid inverted torx heads again.

I pried out the output shafts with very little effort, courtesy of a pry bar. I'm still deciding if I'm willing to tear into the housing any further. I may give it a go, but having no one local who has experience rebuilding one of these units, I'm hesitant. And taking it to a shop would cost more than the diff's worth!

And no insult taken, Tom! Tearing into BMW diffs is a new one for me, so any input is much appreciated.

Tomorrow night, I'll grab a few more pics and post them here. Who knows, it may even document the reassembly of the unit. Here's to hoping!!

Tommy

[tombmwe30]

Tommy,

GO FOR IT...you are just really partially disassembling it then back again...if you want, pm me and Ill give u my cell# and I can talk you through some of it.Way easier than typing..good luck

Thanks for compliment Jerry..

[jmciver]

I guess I will also chime in on Tom's behalf. I know him personally (I get beat by him at local auto-x events.....but not for long ). He really does know his stuff. Welcome to the board, Tom!

[tombmwe30]

Thanks James and your car looks great in that picture.

[Tommy R]

Tom,

PM sent.

Thanks,
Tommy

[Tommy R]

Well, I done did it now. The diff is out of the housing.....

[Tommy R]

Here are the all-new diff bolts. The white paint is just to....ahem.....differentiate them from the older ones. They're not torqued yet. I'll remove the paint after they're torqued.

[Tommy R]

Here's the worst part of the ring gear, finally somewhat visible in a digital pic. I honestly don't think it's anything to be alarmed about. I hope I'm not wrong in that assumption!

Only two teeth actually have chips, though the pic makes it look otherwise. The rest have marks, but they're insignificant.

[Tommy R]

The driver's side bearing race area had two remnants of the speedo sensor.

[Tommy R]

Passenger side was fine. Note none of the bearing races have been cleaned at this point.

[Tommy R]

The bearings look fine, best as I can tell.... Note some of the remaining yellow gear marking compound that hasn't been completely cleaned away as of yet.

[Tommy R]

Pinion looks fine. It's torqued down and smooth, but I bought a new crush sleeve and will likely install it and re-torque it, just in case...

[Tommy R]

Here's a slightly better pic of the piece parts. Pryed the output shafts off easily. Removed the six side bolts per side and twisted the cover and worked it out. Piece of cake. Thanks for the advice, Tom! :

[Tommy R]

BTW, Tom, I noticed you were running in DSP at Nats (as mentioned earlier). I've been co-driving in FSP for the last two years in my buddy's Scirocco (was in CP before that). We'd have placed 2nd and 3rd last year behind Taka Aono if it weren't for some lame ass protests. The cylinder head we were running was legal, but we didn't have the means to prove it. We do now. This year we got seriously boned in the rain. We didn't have Dirt Stockers. We didn't even have Kumhos.

Ah well. I won't be at Nats this year, but look for me in STX with the 325is in '05....

Tommy

[Tommy R]

Forgot to mention I picked up some bolts to replace the inverted torx bolts that hold the half-shafts to the output flanges of the diff. Unfortunately, it looks like the head of the bolts is going to be too large. I'll see if they have any with smaller bolt heads. Hmmm......maybe that's why they used torx bolts from the factory?

[John in Houston]

Good job Tommy! Any chance of you opening up the diff for some additional pictures???

[Tommy R]

Originally posted by John in Houston
Good job Tommy! Any chance of you opening up the diff for some additional pictures???

Oh, hell no. Seriously, I think this is as far as I need to go in order to properly clean everything out. Everything will get further drenched in brake cleaner and the reinstallation will begin.

Who knows, maybe I'll actually put this thing in the car this weekend.....

Tommy

[John in Houston]

Originally posted by Tommy R
Oh, hell no. Seriously, I think this is as far as I need to go in order to properly clean everything out. Tommy

Oh, I know you don't have to go any deeper.... I just want to see more pretty pictures (and I'm curious as to the internal setup)

[Tommy R]

Tell you what I'll do.... :12:

Tonight I'll try to take some very nicely detailed pics of the diff. Can't promise I'll be able to come up with anything worthwhile, but I'll do what I can. Visibility is rather limited in there. :

Tommy

[tombmwe30]

Great pictures Tommy

Im glad you did it and it doesnt look too bad.Hope none of bearings were damaged but if they were it will just be a little noisey.When you reassemble make sure you have a little oil on those big O-rings on side covers or they will be a little difficult. Great to talk to another autoXer.I started out In A-1 scirocco...THEY ROCK. are you using this diff for your STX 325IS
If so and you want some more performance....CHECK your PM. Tom b

[BlueMaxx9]

So Tommy, now that you're all experienced in diff refurbishing, how much would it take for you to clean one up for me

-Bret

[Tommy R]

Originally posted by tombmwe30
Great pictures Tommy

Im glad you did it and it doesnt look too bad.Hope none of bearings were damaged but if they were it will just be a little noisey.When you reassemble make sure you have a little oil on those big O-rings on side covers or they will be a little difficult. Great to talk to another autoXer.I started out In A-1 scirocco...THEY ROCK. are you using this diff for your STX 325IS
If so and you want some more performance....CHECK your PM. Tom b

Hi Tom,

Thanks for the compliment and the feedback/suggestions!

The 'Roc we were running is a '76 model and we did have the hydraulic lifter head. It's now solid lifter (like everyone else's) and is faster. Mark my words, Richard Windberg will win an FSP National Championship in that car within the next 2-3 years. The car's that good. And so is his driving abilities!

Yes, I plan on running this diff in STX. PM's checked. Look for a response soon.

Thanks!
Tommy