Discussion in 'E36 M3 (1991-1999) and E30 M3 (1986-1990)' started by tombance, Jun 10, 2018.
Just an idea but has anyone checked the diff breather on your leaky diffs. On the 210 diff It’s just a small hole on the rear of the casing if I remember rightly, I’ve got to mine so I will check. Anyhow if that gets filled with crud then there is nowhere for the extra pressure to bleed out as the diff gets hot so oil can get forced past the seals.
I’ve had a leaking front seal and one leaking rear seal so far on mine.
This is an issue and often overlooked. my 188mm diff started leaking from the output shafts only a year after they were replaced.
I pulled the diff and was going to replace the seals but noticed the breather was blocked. Since having drilled it out, its not leaked at all.
Good call. Will check it, just to rule it out.
In terms of the diff seals themselves, is it dealership only or were these used on other vechicle?
Did mine while I was crawling around under it.
There is a dimple above the speed sensor connector about 10mm across in the middle of a simple there is a pin hole. This is the breather. Mine was full so the dimple was flush!! It’s an alkward pita to get to.
Cleaned the crud off with a wire brush then used a oring pick to poke out the dirt front eh hole. when that was put I got a bit of copper mains wire and bent the into a poker. And pushed it through the hole until I was pretty confident it was inside the diff. Pretty simple, but hopefully may stop the weep.
I had poked mine through with a piece of wire before all of this, so unfortunately for me that wasn't my problem.
I've driven the car about 500 miles since I resealed it and no problems so far. So finger crossed