Author Topic: Diff output shaft seals?  (Read 2472 times)

Cristian G in Oz

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Diff output shaft seals?
« on: September 08, 2008, 06:32:37 AM »
Hi guys,

After looking Real OEM and a couple of the race car diffs (E30 M3), I have found that there are 2 different size dia output shafts.

I want to replace the seals on the LSD that I bought, but the seals that I got from my local parts supplier got me large ones (@33mm dia).  The ones that are in the diff are smaller.

Can the different seals be installed in the same housing or do I need to change the current seal mounts to the new diff as well as the output shafts?

Thanks

Cristian
1990 318is
Alpine White, M44 head, 3.91LSD and added fun:)

Frankie

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Diff output shaft seals?
« Reply #1 on: September 08, 2008, 09:29:39 AM »
What LSD you have? After you hace checked that information then look at online ETK for the part numbers and see if they fit.

Cristian G in Oz

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Diff output shaft seals?
« Reply #2 on: September 08, 2008, 04:19:53 PM »
My problem is that the diff in teh car looks like the top output flanges and housings (item 4), but the "new" diff looks like item 8 in the lower diagram.

http://www.realoem.com/bmw/showparts.do?model=AF92&mospid=47256&btnr=33_0142&hg=33&fg=10

What is involved in "setting up" the shims (items 10) if they are fitted under the seal housings (items 4 or 8) ?

Is itr just a simple swap over the shims with the housings or do I have to measure up and check clearances on something?

Thanks

Cristian
« Last Edit: September 08, 2008, 04:21:42 PM by Cristian G in Oz »
1990 318is
Alpine White, M44 head, 3.91LSD and added fun:)

Cristian G in Oz

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Sorry, didn't answer your Question
« Reply #3 on: September 08, 2008, 04:25:31 PM »
Quote from: Frankie;56301
What LSD you have? After you hace checked that information then look at online ETK for the part numbers and see if they fit.


The LSD I have bought is a 1:3.91.  I think it came out of an early 318i.
My car currently has teh standard 1:4.11 non slip unit in it.

I am happy to go with teh loss in acceleration as the new diff will give me better legs and lower my revs (just a little) for freeway cruising.

Cristian :)
1990 318is
Alpine White, M44 head, 3.91LSD and added fun:)

Cristian G in Oz

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Finally fitted up my new diff. Answered my Question.
« Reply #4 on: January 27, 2009, 09:00:57 PM »
Quote from: Cristian G in Oz;56291
Hi guys,

After looking Real OEM and a couple of the race car diffs (E30 M3), I have found that there are 2 different size dia output shafts.

I want to replace the seals on the LSD that I bought, but the seals that I got from my local parts supplier got me large ones (@33mm dia).  The ones that are in the diff are smaller.

Can the different seals be installed in the same housing or do I need to change the current seal mounts to the new diff as well as the output shafts?

Thanks

Cristian



I ended up changing the seal carriers (the bits that bolt onto the side of the diff and the output shafts go through) over to the LSD. I also took over the drive shaft flanges from the old diff.

So far no leaks, so I'm guessing I got things right.

The next quetsion I have is:
On the seal carriers there is a tab that sticks out. Should this be at the top or the bottom of the fitting. The Bentley (sp??) manual does not show any pictures and also describes changing the seals without tacking the carriers off.

My only thought is that as there is a hole on the inside of the carrier that lines up with the tab it is either a drain for oil splash or a vent for the seal cavity. Not sure which one.:confused:

The diff that I fitted them to had them at the top but I didn't take any notice of the diff that was in teh car until it was too late:mad:

Can anyone shed some light in this?

Thanks

Cristian
1990 318is
Alpine White, M44 head, 3.91LSD and added fun:)