Signs of rear diff failure?

**SciroccoTDI** · 04-17-2009 06:12 PM

Hey guys, new S4 owner here, a well cared for stock 2000 that I am fixing a few things just due to age/wear (she has 130k on the clock).

I had the rear diff mount that was totally shot upgraded to a Apikol, and now at speeds above 40 mph I can hear the rear diff, a higher pitch whine. Another symptom is driving in the snow, when I spin the tires, the ass end ALWAYS slides out towards the passenger side (with wheels straight, flat surface). Are these two symptoms signs of a dying diff, or is hearing the diff normal and I just need a 4 wheel alignment?

Thanks in advance guys!

-Eric

**a4_1.8t_01** · 04-17-2009 06:39 PM

I have the exact same problem after switching to apikol. I looked underneath my a4 and found the center bearing support is kinda sloppy. I dont know what kind of fix there is for that.

**SciroccoTDI** · 04-17-2009 06:43 PM

Originally Posted by a4_1.8t_01

I have the exact same problem after switching to apikol. I looked underneath my a4 and found the center bearing support is kinda sloppy. I dont know what kind of fix there is for that.

I should note, that the ass end sliding out under power towards the pass side was there before and after the Apikol. I have NO idea if they are related...hence the thread :)

**SciroccoTDI** · 04-20-2009 12:42 PM

No responses, sad.

Well, got alignment today, they found one of the right rear lower link nuts backed out about halfway, that would certainly explain the minor vibrations at speed and the weird tendency for the ass end to slide out. Drives nice now.

Still have high pitched whine from the rear diff at 40 mph or above...suspect bearing damage, found a receipt in the PO records with diff seals being done, I suspect he ran it low/dry for a period. *sigh* Oh, and both EGTs throwing codes....weeee. I will get this sucker fixed up, just gonna take some time.

**Dimcorner** · 04-20-2009 12:47 PM

I have a whine above 60mph and stops at 70mph (only under load). Someone at AW said that replacing the bearings where the drive shaft connects to the diff solved it.