Tech Article Title Author Date
Replacing the Rear Differential Mount Nick Gustas 2004

You'll need

  • T50 torx
  • T45 torx
  • VAG1359/2 universal support :P
  • PN: 8A0599133B at minimum, replacing all bolts is a good idea too.

Overview of area, this will serve as before and after pic. Clean aluminum thing is the culprit today.



To begin, remove 4 bolts on aluminum crossmember, two are by exhaust and hold exhaust hanger. Exhausts other than Borla may require removal. YMMV.



Removed crossmember, this and mount are amazingly light.



With crossmember out of the way, remove four bolts holding mount to diff.



Naked bottom of diff to give an idea of where the bolts in the previous pic are.



Reason to watch knuckles is that pesky gas tank strap. It's dull, I knew it was right there, but the first bolt caught me off guard anyway when it broke loose. Good thing it was cold out, didn't hurt a bit. Got blood all over though. Lot more blood when I went inside and unfroze my fingers. :)



Old and new, side by side. No significant visible damage to old mount, but it was not as stiff as the new one.




Old mount in the distant past would allow diff to rub and make scraping noise under first gear accel. Would also bang occasionally under sudden driveline load. Here is the mark.



I cleaned the area and re-undercoated the mark, all I had was 3m black rubberized so it doesn't match. If you need to do this make sure you cover the diff flange so excess undercoating spray doesn't knock it out of balance.



Side overview.



Torques as best as I could decipher from Bentley.

40NM long bolts through crossmember to body.
23NM exhaust mount bolts to body.
50NM mount to diff.

Important!
When reassembling, use a jack or similar AOA approved device to lift the diff and exhaust to the proper height. DO NOT pull them into place using the bolts, they may strip out if you are unlucky.