What's the Widest tire that can safely be put on a 19" X 8.5" Factory GT wheel? I have 245/45-19 on all 4 corners right now.

 

My snow tires are 255/40-19 on factory 19x8.5 rims.

 

I had a 255/40-19 on my 19x8.5 and it was fine.

 

I wouldn't recommend any wider than 255's for 8.5" wheels..

 

Go to tirerack, select a tire, look at the listed specs. It'll tell you wheel widths for each tire size.

 

The Performance Package V6 has the same wheels as the CS/GT (different color is all) and comes with 255/40r 19's. I had 275/40r 19s on mine and they handled like crap so not recommended. I went up to a 9 inch wheel for those tires.