I have a 2001 Excursion with 315 75R16 tires on stock 16x7 wheels. I know that they should be on a wider rim with less rear offset or backspace. I think stock is 4.5. They rub a tad on the front leaf springs when I max out my turns. I was wondering what width rim would be the best and what rear offset would work best. Perhaps just the wider wheel with the same 4.5 offset will work simply because the tire wont bulge out as much as they do on the narrow wheel?

 

Keep in mind you may move the point of contact off the leafsprings and into the wheel well liner and bumper corner.

I went from 16x8's with stock backspacing to an 18x10, -25mm (basically an inch) and had to trim the bumper corner about an inch. The wheel well has self-clearanced over time.

 

We were running 35/12.5R16 on stock wheels when we bought the truck. Had the slight rub on the spring...no biggie. We are now running 315/75R16 on 16x10 with an extra 1/4 inch offset. Wicked rub on bumper and rear inner fender. With any spirited driving it becomes worse. Take the spring rub. No body damage there and we had a much tighter turn before.

 

I forgot to mention that I have a 3" lift, so possibly there will be no rubs anywhere if I go with wider wheels?

 

We are running a 4 inch Pro-Comp lift. Still major rubbing on the bumper and fender with the extra offset. The wider wheel isn't helping the clearance but fits the 315 profile much better than the stock 7 inches.

 

I have a 4", same suspension on the 315/75 16's as now with the 18x10's. I had to trim the bumper corner about an inch going to the 18's as they're wider and more offset that the previous 16's. The inner fender just kind of clearances itself.