[s-cars] Shimmy -- please help diagnose

[tim rad]

My symptoms were exactly the same as yours....

Subframe bushings are about $100 and a dealer only part.  I just put
mine in 3 days ago and it took me about 5 hours to do it myself first
time.  With a working air chisel, I think I could have done the job in
2-3 hours.  This cured most of the problem, but I noticed that one
shock was leaking oil badly, and I'm also suspicious of the ball
joints.  Also you should check your tire balance.  I had some tires
that were a little off and it was worse until I rebalanced them.

Lower control arms and ball joints are one unit and would cost about
$350 per side for parts from the dealer.  See below for more resonable
cost parts:

http://www.germanautoparts.com/Audi/S6/Suspension/60/1

Shocks are an even bigger SHOCK.  The dealer quoted me $550 each for
the Boge shocks and this was after he claimed he reduced his margin to
almost zero.  See the Boge shocks:

http://www.germanautoparts.com/Audi/S6/Suspension/188/1

I haven't purchased from this store, but others have recommended them.
 I am hoping these are OEM parts, and I will replace shocks and lower
control arms as well with the goal of a tight steering front end.

best of luck....
Tim
93 S4 150K miles