Greenmachine99

Has anyone seen a 2006 A6 with 255/35/R19's? I got a great deal on a set of S5 rims and am not sure if the tires will be a little to big.

bakes

My factory tire size is 245/40/18. When you compare 255/35/19 to them the actual difference is 1.2% bigger.

So when your speedo reads 60mph you are actually going 60.7. Total circumferance increase is only 1inch and diameter increase is only .3 of an inch.

You should be fine with those tires on. Post pictures if you get them!

Dr Cykosis

I have a 2007 A6 with 255/35R19. No problem at all.

Spartan300

I don't think it would be a huge problem. The proper tire size for the V6 A6 is 245-35-19 and for the V8 A6 is actually 255-35-19.

Your biggest concern should be the bore size of those S5 wheels. The hub size of the B8's is (66.6mm) therefore bigger versus the (57.2mm) for the A6 (not 100% though for the A6 but 95%).

Therefore hub centering rings (not sure if available for stock wheels) would be required otherwise you will feel some vibration while driving.

ARM

I find my speedo reads above my actual GPS speed by about 2%. I am using the standard tire size for my TT. My tires are 25.7 the TT can take up to 26.3" diameter. The 26.3 would actually give me a closer speedo reading to the GPS, you may find the same result.

AR

Just_G

speaking of Speedo being off. I am using the factory USP set up on my audi and at 130 (according to the speedo) i am only doing 120 (according to Garmin). Since the wheel size is factory, im confused why the difference on my car.

Stevelev

Although 10 kms off is high, it seems that all car manufacturers calibrate their speedos to be off by at least 3-4 kms/hr (ie: speed is slower than shown). I would think this is for safety/ liability purposes. I too have used a Garmin and seen this in my Audis, a BMW and Mercedes.