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LVP
07-31-2010, 06:52 AM
Hi guys,

My main diff seal is leaking. Is it possible to remove the cover in place, use a gasket material and put the cover back on? Or is a removal of the diff necessary?

Thanks!

sloveniaboy
07-31-2010, 02:07 PM
Hi guys,

My main diff seal is leaking. Is it possible to remove the cover in place, use a gasket material and put the cover back on? Or is a removal of the diff necessary?

Thanks!

it is necessary to remove diff. if you've done this once before, you'll realize the hardest part of the job is finding a store that carries the etorx socket (E12) required to remove half shafts from diff.

tons of DIY's out there....

here's one for reference
http://www.e36-tech.com/forum/diy-e36-differential-swap-2466.html

doogee
07-31-2010, 03:39 PM
it is necessary to remove diff. if you've done this once before, you'll realize the hardest part of the job is finding a store that carries the etorx socket (E12) required to remove half shafts from diff.

tons of DIY's out there....

here's one for reference
http://www.e36-tech.com/forum/diy-e36-differential-swap-2466.html

He's right. The only place a managed to find the E12 socket was princess auto. Pull the diff, take the cover off and use "Permatex Right Stuff"

You can get it at napa, maybe canadan tire. It's expensive but really good.

You don't have to change the diff fluid if you rest the diff on the input shaft. But it might be a good time to change the fluid.

I'd use Redlne 75w90 or 75w140 if you can find it.

LVP
07-31-2010, 06:25 PM
Thanks guys. Is there a different fluid for LSD vs non?

doogee
07-31-2010, 07:00 PM
Thanks guys. Is there a different fluid for LSD vs non?

Yeah LSDs need then slip additive in the fluid. So if you don't have an LSD then you don't need to worry.

LVP
07-31-2010, 08:57 PM
I've got an LSD. From what I can find, the 75W90 is the correct weight, not the 75W140.

Is it better to make the gasket using the Permatex stuff, or get a new gasket from BMW?

Other than the pita of getting it out, the procedure is relatively straight forward. Some have suggested replacing the shaft bolts so I'll do that in the meantime. How hard are output shaft seals? I may do those too while it's off and out.

Cheers!

Dr. Flyview
08-01-2010, 01:12 AM
What doogee said. We had to do this to my leaking LSD back in the spring, worked wonders. BTW from what we found at the time, 75w140 is right.

LVP
08-01-2010, 08:24 AM
Interesting on the fluid weights. I looked in my Bentley manual and it call for BMW SAF-XO (non-LSD) or BMW SAF XLS (LSD). From Redline's site, they cross ref this to the 75W90 (see bottom of the page) http://www.redlineoil.com/news_article.aspx?id=13

Turner also recommends this weight of fluid, as do numerous other DIY's. Unless someone has info otherwise to support the 75W140, I think it should be the 75W90.

There is an Amsoil dealer nearby, so I'll likely go with their fluid. Need to source the tools (14mm allen and E12 socket) first.

Cheers!

LVP
08-09-2010, 07:43 PM
After several discussions with the Amsoil people, the 75W140 is the correct fluid for the LSD's. They are clearing up the info in their systems.

I pulled the diff to do the shaft seals and main seal. Much, much easier doing it with the diff out of the car than trying these jobs with the diff mounted.

Diff is filled - I'll leave it sit for a day to see if the main seal leaks, but it looks like I won't really see how well my shaft seal install was until I run it and get it hot (the shafts sit higher than the top fill plug).

Cheers!

Axxe
08-10-2010, 02:22 PM
FYI, that's the cover gasket. Seal refers to input or output shafts.

LVP
08-10-2010, 04:07 PM
Correct - main gasket, output shaft seals. Input shaft I left alone.