Swapping Diff Cover in Situ

[Cubieman]

I am wanting to replace the rear diff cover to get new OE bushings/different bolts in place and wanted to know any tips/tricks when doing this job while the diff is still in place.

It looks pretty tight up there but there's no way I should need to remove the entire diff right? Looks like the sway bar comes out of the way and I'll use something to support the diff while the bolts are out.

Some torque specs would be great as well if anyone happens to know them off the top of their head. Trying to get this done tomorrow night as an unexpected trip has come up and my research time is being cut down significantly.

I've purchased some Loctite 5970 for the sealant, I've only got one 50ml tube which makes me a bit nervous as it seems like I could run short if I make the bead too wide. Is any off the shelf sealent such as Permatex black RTV acceptable?

Thank you!

[mrgizmo04]

Yeah you can do it with diff in.

For the rear mount bolts i had to use an 11mm open end wrench, my side swivel/socket/extension/ratchet were not fitting well. Remove the swaybar bushing brackets.

Diff cover bolts torque is 33 lb ft, the 2 mount bolts are 15 lb ft + 90 degrees (I think this ends up around 50 lb ft).

I've used rtv without the paper gasket for a long time with no leaks and diff sees high temps and track.

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[oceansize]

I've purchased some Loctite 5970 for the sealant, I've only got one 50ml tube which makes me a bit nervous as it seems like I could run short if I make the bead too wide. Is any off the shelf sealent such as Permatex black RTV acceptable?

Unless you go bonkers with that sealant you aren't going to run out. I had the 50ml tube when I did my rear end refresh. Really good stuff.

[M3GA]

About to do the same job, but bought a new paper gasket. Anyone refresh without a liquid gasket and went with paper gasket?

Should I do both? seems overkill.

Should I expect the new paper gasket to hold up like OE gasket?



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[Tbonem3]

Yes, paper alone is just fine.

[Tbonem3]

Cross tighten the cover bolts.

[Cubieman]

Hey, what are the torque specs on the sway bar bushing clamps?

[oceansize]

Hey, what are the torque specs on the sway bar bushing clamps?

16 ft-lbs

[Cubieman]

Thank you.

[bigjae46]

I had the 50ml tube when I did my rear end refresh. Really good stuff.

Bro...careful what you say around here. I’ll give you a free pass this time🤣🤣🤣


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[Shadytype]

If you gotta ask big man, you probably cant afford it.....

[oceansize]

Bro...careful what you say around here. I’ll give you a free pass this time🤣🤣🤣

Just took a second look at what I wrote, not good, not good at all LoL.

[Cubieman]

Also, one more quick question, with the Loctite 5970 I assume I treat it like I would black RTV for my other vehicles.
- Lay down a bead (surrounding bolt holes)
(how thick of of a bead would you lay?)
- Wait 10 minutes for it to "tack up"
- Finger tighten bolts in criss cross pattern
- Wait 30-45 minutes
- Tighten bolts to torque specs

Sound alright? The instructions simply say to assemble parts within 15 minutes, I haven't done this job on the M3 yet and new jobs make me nervous, plus I don't want to waste any of that pricy fluid. Thanks for all the help guys.

[oceansize]

Also, one more quick question, with the Loctite 5970 I assume I treat it like I would black RTV for my other vehicles.
- Lay down a bead (surrounding bolt holes)
(how thick of of a bead would you lay?)
- Wait 10 minutes for it to "tack up"
- Finger tighten bolts in criss cross pattern
- Wait 30-45 minutes
- Tighten bolts to torque specs

Sound alright? The instructions simply say to assemble parts within 15 minutes, I haven't done this job on the M3 yet and new jobs make me nervous, plus I don't want to waste any of that pricy fluid. Thanks for all the help guys.

I let it tack for 5 to 6 minutes and then finger tight. Torqued down by 15 minutes. This stuff sets quicker but also seems more pliable which should be great in a diff, can see why they used it.

Edit: I would say I used, roughly, .35 inch bead. Definitely do not need more than .5 inch bead.

[Cubieman]

So the 2 rear diff bolts that hold the diff to the subframe are 50 ft lb then? Having trouble finding this one on paper. I see newtis says 20nm + 90°.

https://www.newtis.info/tisv2/a/en/e46-m3-cou/repair-manuals/33-rear-axle-rear-wheel-drive-guide/33-10-rear-axle-final-drive/5XGnMyr