Just got 2011 G37XS came with 19" stock rims, not sure of width maybe 8.5" or 9". OEM tire size is 225-45-19 I understand must have same size on front and back, question is will 255-40-19 work on stock rims and not have rub issues? Anyone used this size

 

Most run 245/40/19 myself included...but I'm not saying that 255 won't fit.

 

245s are more common but the 255/40/19 will be quite a bit closer to OEM diameter, should fit OK on an 8.5" rim but obviously better on a 9".

 

Will pull wheel off front and back to see if same or 8.5" and 9" not sure if 255 is ok on 8.5"

 

I run 245/40/19 on the front and 275/35/19 on the rear. The fronts are less than 1% smaller than originals. The rears are 0.5% smaller. One of the benefits to running these sizes is having more rubber on the ground, especially important for RWD cars with power. You will also find that there are many more tire brand options with these more popular sizes vs. the originals.

You can check out different size combinations at Tire Size Calculator - Tire & Wheel Plus Sizing

 

Im planning on running this.. Are you using spacers or anything?

 

I always bump the width up a size when replacing tires and have yet to have an issue.

Might be different if you are running an AWD; those seem to be real sensitive, from what I've read here...