Leaking Diff with a bit of a whine

Post Fri Jul 22, 2005 7:48 pm

Had a look under the car the other day after noticing a bit of a whine/drone coming from the back end. Noticed that diff appears to be leaking from one of the driveshafts. I've checked the oil level and its ok - some comes out when I take out the filling plug.

Have I got a problem with one of the diff bearings. Any help/ideas gratefully received

Post Fri Jul 22, 2005 10:59 pm

Nothing unusual for E30 diffs to whine a bit. They can go on happily for tens of thousands of miles like this.
Also not unusual for a diff output shaft seal to leak a bit.
Bit more worrying if the two started at the same time.
Output shaft seal is easy to change. - Undo ring of bolts holding driveshaft to the output shaft, lever output flange out of the diff 9snap ring), and you will see the seal. Prise out and replace, push output flange back in and connect up the driveshaft.

Post Sat Jul 23, 2005 3:15 pm

Was just a bit concerned as I've only had the car a couple of weeks and I'm just sussing out the noises it makes - the scorpion exhaust gives it a bit of a burble as well not like my standard Touring.

Cheers for the advice on the seal, I might change it see if that solves the problem. G/box is leaking as well which is a bit more of a concern but engine is dry as a bone with only 60,000 miles on so I'm hoping it's nothing major.

Post Sat Jul 23, 2005 3:52 pm

Only concern with the gearbox leak (within reason) is if the oil gets on the gearbox rubber mounts and dissolves them.
Oil quite often leaks past the selector shaft oil seal at the top of the back of the box, as well as the output shaft.
Both are fairly easy to change, especcially if the exhaust is off for any other reason.

Post Mon Jul 25, 2005 10:42 am

The whine is pretty normal, just usual wear and maybe a low fluid level. Any droning is probably indeed a bearing going out

.

Good news is that it probably will hold for a long time. Mine has been making droning sounds for the past 20k miles diagnosed to be coming from one of the bearings and altough it's really loud and annoying now above 60mph it still hasn't fallen off...

- Rick

Post Mon Jul 25, 2005 7:27 pm

rickk,
Yeah, i'd like to fix the thing before it drops off! I suspect I have a bearing problem, the droning is getting worse and I did notice it when my mate bought the car first. Might try wheel bearing first though?

Thanx for gearbox advice, i think it probably is the output shaft seal and i can see some oil coming from the top around the selector switch. Gearbox was recently taken to bits and all the seals replaced so with a bit of luck they might bed in -

I've been checking the oil level with the engine running after each drive and it seems ok.

Post Mon Jul 25, 2005 7:56 pm

dannosail wrote: Yeah, i'd like to fix the thing before it drops off! I suspect I have a bearing problem, the droning is getting worse and I did notice it when my mate bought the car first. Might try wheel bearing first though?

Sure, by all means, both sound very much alike but the wheel seems to be reacting more to turning while the diff will react more to ac/decelerating.

But it's probably hard to tell the difference if you never experienced both....

- Rick

Post Mon Jul 25, 2005 8:00 pm

If you have a noisy diff and it is getting on your tits and you are looking at replacing bearings, my old man reckons it will cost you more in bearings and the seal kit than it would to source a decent second hand one, LSD boys not included here by the way!

I haven't priced the bearings mind you

Post Tue Jul 26, 2005 5:33 pm

I'll swap the wheel bearing see if that solves.

As for the diff, my bro' just took the diff on his Audi S2 to pieces and still had a lot of trouble solving the problem - I think a second hand diff is probably the easiest way to go.

I'll see how it goes. Cheers for the advice.