A construction outfit I used to work for used 9.00X 20 tires on a couple of 65 C-60 dump trucks they had,and they worked,but had very little clearance around the front fenders,bumper corners,and steering linkage,and on the rear they nearly touched when the trucks were empty;I think the only thing that saved them from continuous blowouts was the fact the trucks were never used outside of town-too slow. A set of 8.25's should work fine on the rear,but still might have some clearance problems on the front,depending on your ride height,how the fenders hang,and what type front suspension you have.
Speed
