Posted this in the e36 board, but no one's responding, so I'm asking people here that actually know what they're talking about. So here goes:

Got everything done on the race car this past week including swapping my 3.38 for the Spec E36-friendly 3.15 LSD out of a '95 M3 and noticed a leak at the pinion shaft, so I replaced the pinion seal including new lock nut and the diff is still leaking from the same spot. Any ideas what it could be? Is it possible that I got the wrong pinion seal? I told my parts guy it was for my '95 325is and that's it. Everything looked fine with the initial install, so I'm at a loss here. Torque on the nut was per Bentley specs at 129 lbs., IIRC. I replaced #3 and #5 on this diagram:

http://img.photobucket.com/albums/v71/BimmerDawg/10.png?t=1202913779

Also, I cross-checked realoem.com and verified that M3's and 325is' have the same part number for the pinion seal, too. I'm at a loss here. :help

Are we talking drops or serious seepage? (Tpat, keep the jokes to yourself)

Are we talking drops or serious seepage? (Tpat, keep the jokes to yourself)

:rofl:


:shifty

What?

Are we talking drops or serious seepage? (Tpat, keep the jokes to yourself)

I'd say it's pretty serious as there's a small puddle that collected overnight.

Possible that you've got the seal in canted?

Possible that you've got the seal in canted?

Asked my tech and said all was good with the install.

By any chance were you able to "dry fit" #1 into #5 before the install, just to verify its a correct fit..... where the rubberseal has "some" pressure from the coiled spring inside the seal......(in case you accidentally got the wrong seal in the box.....).

(Question.....they didnt give you #8, crush coller on the rebuild? And I was asking that because typically you'd wanna replace that also after the torque has been done 1x)

If the seal was originally bad due to dirt/grime ingress then the seal surface on #1(in your diagram) will be polished and/or eroded to a point where it will not seal. Polishing a surface will make the leak worse, not better. You could also have an out-of-round condition on #1 as well if it was originally out of alignment with the pinion splines, but that would be hard to do.

By any chance were you able to "dry fit" #1 into #5 before the install, just to verify its a correct fit..... where the rubberseal has "some" pressure from the coiled spring inside the seal......(in case you accidentally got the wrong seal in the box.....).

(Question.....they didnt give you #8, crush coller on the rebuild? And I was asking that because typically you'd wanna replace that also after the torque has been done 1x)

Nope, no #8.

If the seal was originally bad due to dirt/grime ingress then the seal surface on #1(in your diagram) will be polished and/or eroded to a point where it will not seal. Polishing a surface will make the leak worse, not better. You could also have an out-of-round condition on #1 as well if it was originally out of alignment with the pinion splines, but that would be hard to do.

That makes sesnse. Hopefully that's not the case. My tech's gonna drop the diff and replace the seal again, just to make sure.

That makes sesnse. Hopefully that's not the case. My tech's gonna drop the diff and replace the seal again, just to make sure.

It must be nice to have a tech to do your bidding. :shifty

It must be nice to have a tech to do your bidding. :shifty


I tell my tech what to all the time. Usually, he tells me to go F myself and hangs up.

:(

It must be nice to have a tech to do your bidding. :shifty

Doesn't suck.

I tell my tech what to all the time. Usually, he tells me to go F myself and hangs up.

:(

Sounds like Wael. :rofl

Sounds like Wael. :rofl


Ding ding ding!


Luckily...I know where he lives!!! :evil2

Ding ding ding!


Luckily...I know where he lives!!! :evil2


Unfortunately, he knows where you live! :mad

Unfortunately, he knows where you live! :mad

:confused

Wael...is that you? :wave

Nope, no #8.



That makes sesnse. Hopefully that's not the case. My tech's gonna drop the diff and replace the seal again, just to make sure.


If he's gonna do it again...... You may want to get the #8 (if it is a crush coller). Once they are meant to be used 1x and "crush" in size......(someone could jump in and add on this one).

Geordie, maybe this will help, in the repair instructions it says to check 2 different parts for wear.
http://img136.imageshack.us/img136/2663/page1wy0.jpg
http://img352.imageshack.us/img352/1218/page2sf7.jpghttp://img352.imageshack.us/img352/3074/page2zq1.jpg

http://img136.imageshack.us/img136/7877/page3hh0.jpg
http://img178.imageshack.us/img178/1334/page4ot6.jpg

aahhh where can i get a detailed manual like that ---^, I look at my bently manual sometimes and leave more confused then when i started reading o_O

I was asking that because typically you'd wanna replace that also after the torque has been done 1x)

NO, you dont need this.

If he's gonna do it again...... You may want to get the #8 (if it is a crush coller). Once they are meant to be used 1x and "crush" in size......(someone could jump in and add on this one).

Yes. IT is indeed a crush coller. And NO you donot need to replace this..... Dont ask me why!


aahhh where can i get a detailed manual like that ---^, I look at my bently manual sometimes and leave more confused then when i started reading o_O

BMW TSI

To the OP:

If the second seal doesn't fix it. I can rebuilt you a new diff, w/new clutches, Cryo ring, pinion & spider gears and any ratio for a desent price for your race car.

I havent read the rules for SE36 but I thought I heard you should have a 3.91.

I havent read the rules for SE36 but I thought I heard you should have a 3.91.

3.91 will be for the '08 season, starting in '09 a 3.15 is the mandated SpecE36 gear.


AFIAK, the crush collar is only going to be replaced when pulling the ring and pinion out - it's on the inside of the diff, not on the outside where it can be accessed by removing the flange.

I'd agree with the others - check the seal, make sure you gt the right seal. Also, check the surface of where the outside of the seal meets the diff case, as there could be a large gouge there allowing fluid to leak past the seal.

Also, check the play in the pinion. It's possible that the bearing is shot and allowing excessive play, which will most definitely cause a leak past the rubber inner part of the seal (the part that touches the pinion). If the bearing is good, I'd use a bit of grey RTV on the outer metal part of the seal where it meets the diff case, to prevent a possible leak there.

Good luck!!!

The poor person's(including all 3 genders here.. :) ) Way to check for wear is to drag a penny down the length of the shaft and feel for catches or drag. If you feel anything then the seal surface is worn too much.. I think that was in a GM service manual I read before using it to start a bonfire.

The poor person's(including all 3 genders here.. :) ) Way to check for wear is to drag a penny down the length of the shaft and feel for catches or drag. If you feel anything then the seal surface is worn too much.. I think that was in a GM service manual I read before using it to start a bonfire.

Huh??? :confused

I'd be very, very surprised if the pinion shaft itself had wear.

Not the pinion gear shaft, the seal surface of the shaft on the yoke(#1 in the diagram in the first post). I've seen it many times on various vehicles. It happens when dirt gets into the seal and grinds away. Once the rubber starts to erode, more dirt gets in and the process speeds up.