I am about to take delivery of my new 2007 S8 and have never had 20" wheels before.

Can anyone make recommendations about what to do about snowtires? Are there even snow tires for 20" wheels? Do they work (with potholes and all)? Should I get a second set of 18" wheels with snows? If so, would I be able to fit my S4 snows on those, or would would it be a different width?

I am sure my dealer will have answers, but I would rather ask here first.

From TireRack - Looks like they offer one Winter option. Click below:

As for substiting other Audi wheels, check carefully as the massive torque produced by an S8 probably implies that only certain wheels are officially "approved" by Audi (meaning anything that an A8L-W12 is compatible with should be OK with an S8). Good Luck!<ul><li><a href="http://www.tirerack.com/a.jsp?a=AR4&amp;url=%2Ftires%2FCompare1.jsp%3Fwidth%3D 265%252F%26amp%3Bratio%3D35%26amp%3Bdiameter%3D20% 26amp%3BsortCode%3D59950%26amp%3BminSpeedRating%3D V%26amp%3Bratio%3D35%26amp%3Bwidth%3D265%252F%26am p%3Bd

<center><img src="http://www.fourtitude.com/gallery/generated//Audi/A8-S8-V8%20(D1,%20D2%20and%20D3)/A8%20-%20D3/3.2/003__scaled_600.jpg"></center><p>
I have had great success with the Blizzak LM-22s on Audi 18" 5-spoke wheels. The 255/45VR18 size is load rated for a W12 so an S8 should be no problem. One thing you will notice is that the ride quality is more plush with the 18" wheels; something to be thankful for given the bumpy winter road conditions.

The picture above shows what an A8 D3 looks like with 18" wheels.

The only thing I am not sure on is brake clearance so make sure you check what wheels will fit with the S8 brakes.