on the back of my truck i have a 285/70R17 BFG allterrain...and my other tire was bald discount tire gave me a free tire but its a 265/70R17 Cooper...is it safe to drive on the highway like that...ive been driving it around town and i dont feel like shake or anything...thanks for all ur help...

 

Matt, I would not keep it on too long. Different height's of tire on same axle may cause problem's.

 

yeah its only goin to be on there for a month till i get all new nitto's...but is it safe on the highway?

 

i would get if off as soon as you can. could potentially tear up your rear end. the shorter tire has to rotate faster than the taller tire to maintain the same speed. almost as if you are driving in a circle constanly

 

Swap it with one of the fronts. As long as you don't engage 4wd, there will not be a problem.