Tires- size change ?

Reason I'm asking the question about this tire size change is because my husband has a 2010 mustang, & he wants new tires. If his old tires fit my 2011 Buick LeCrosse I would just pay him what I was going to pay the tire place & let him put they money toward his new tires that he wants.

Fit I don't know but the sizes from your husbands Mustang will keep your speedometer within 1% of the origianal tires. The potential problem is the larger cross section of the tires might rub.... If you put the smaller tires on the front (255x45) that tire is about 1 " wider at the fat part than the original tires, which means 1/2 inch toward the back and the other 1/2 toward the outside. When you turn the front it could rub. The size you want to put on the back is 50mm wider than the originals which is almost 2 inches....since the back tires do not turn like the front you might be ok. I do not know of any site that will tell you the max size wheels that will fit on each model car. you could put your car on a drive on lift and measure how much clearance you have both front and rear.

That much of an increase is pushing it. Mount one of each size and check the clearance. Used tires are worth almost nothing but that is between you and your hubby.