Fattest rubber on stock M Sport 8.5" wheels ?

[nuck]

The car came with Contisport Contact2 runflats I think but the dealer replaced them on road hazard warranty with Goodyear Eagle LS-2 RF and these are a truly crappy tire. All season in name only

On Tirerack's site I found a non RF:
Continental Extremecontact DWS 06 which score way higher in every area at half the price. I want to go up a size so it looks like the 255s will work on an 8.5 wheel. They are .3 taller than stock and about .8 inches wider. The car is stock height. Can I expect any problems? Thanks for any responses.

SIZE UTQG MAX.
LOAD Max. Inflation Pressure Tread Depth Tire Weight Rim Width Range Meas. Rim Width Sect. Width Tread Width Overall Diam. Revs. Per Mile Country of
Origin*

255/40ZR19
100Y XL
560 AA A 1,764 lbs. 51 psi 10/32" 25 lbs. 8.5-10" 9" 10.2" 9" 27" 769 SK

[White94RX]

You list an x-drive F10 in your profile. Does your vehicle have the same size front and rear? Or are they larger in the rear? If you have a square setup, you should be fine as long as all the tires are the same. That being said, I still wouldn't deviate from the factory sizes. Don't want to throw off the speedometer. If you've got staggered tires, absolutely do not change anything or you risk damage to the transfer case.

What exactly are you trying to accomplish? Just more rubber on the road?

[nuck]

Thanks for the response. Yes all four tires are the same size. You have it right, I just want a bit more rubber than stock. The height different based on the speedo calculator I used says only less than a 1mph increase in actual speed at 55mph which is negligible. I have also have read that the F10 speedo reads about 3% faster than radar clocked speed so, if correct, this change would only reduce the inaccuracy. Do these cars throw codes with a change in tire height? Are there any issues with bigger rubber and tires rubbing?

[White94RX]

Since you're planning on changing all four with the same size, you shouldn't have any issues or codes. And for rubbing, I doubt with such a minor change you'd have any issues. Maybe if the car was lowered or something. There's plenty of wheel gap.

One thing I didn't think about was the inside sidewall of the tire rubbing the strut on the front suspension......