NOTE: THE FRONT & REAR SECTIONS OF THIS WRITE UP, AS WELL AS ALL THE PICS, ARE NOW IN THE TECH SECTION. PLEASE GO THERE.

http://www.audiworld.com/tech/wheel28.shtml

I've seen a couple of suspension install how-to's, notably Piggie's in the S4 forum and the one in the tech section by Rich Letsinger. While they are very helpful, the lack of pics imho limits their usefulness. This write-up is intended to 'fill in the blanks' and help out people who have never done something like this before.

Although I've done suspension work on cars before, by no means am I an expert. I get by. I'm trying to provide as much helpful info as I can, but it's certainly possible that I've left stuff out and/or made mistakes. I may be calling something a doo-hickey when the proper term is actually whatchamacallit. If any sharp-eyed professionals or talented amateurs out there see anything I've done wrong, please let me know.

This write up covers H&R Streets on a 2001.5 S4. If you're working with a different combination, it's possible not everything applies to your setup. Also, the torque values listed are from the Bentley manual, and are intended for use with the stock parts. I used them without any problem on the H&R's, but if you have more exotic/expensive coilovers, you may want to check if the manufacturer has any special recommendations. There are also a couple spots where the manual says to use new hardware, and these are noted as well (FWIW, I just re-used the old stuff). Caveat Emptor.

Due to length, the write up will be in three parts: this general info bit, the fronts, and the rears.

I used the following tools:

Floor jack
Audi jack from the trunk (for when the car got lower than my floor jack could go :-P)
Jack stands
Lug wrench
Wheel chocks
Screwdrivers, one large, one tiny
Combination wrenches, 16,17,18,19,24mm
Sockets, 13,16,17,18,19mm
Deep well socket, 19mm
3/8 drive ratchet and various extensions
Torque wrench
6mm allen wrench
Vise grips, round-jawed
Ball peen hammer
Rubber mallet
Punches, various lengths/diameters
Spring compressor set
Spanner wrenches (included in H&R kit)
Tape measure
Needle nose pliers
Exacto knife
Six other things that I'm probably forgetting...

Even if it's your first time, you should be able to do all four corners in one day easily. Just take your time and be careful.

Once you're finished, there are a few things you'll probably want to do. If your brand of coilover is subject to corrosion, put some light grease on the adjusting threads. Drive the car around for a week or two and let the suspension settle, then re-adjust the ride height to your taste. When that's done, I would strongly consider going in for an alignment.

Good luck.