What size wheels and tires can I use?
 

I have an 2004 f150 supercrew with no suspension modifications. I am curious as to what size of wheel/tire combo I can go with if I install a leveling kit? I have been told 325/60/R20 will work. If someone out there could help in solving this dilemma I would greatly appreciate it.

4x4? So are you wanting 20's? I think that tire is going to be a bit big (35x13)

If it's a 4x4 without any major modifications you could fit around a 9'' rim with around 5-5.5'' bs and a 33'' tire. Or something almost identical to oe specs and 35's (35x12.50 or 35x11.50). There are some guys trying out some new stuff recently that looks good but requires a significant amount of trimming, they will chime in.

I agree.

Those tires would be to big on a 20 inch rim. I just put the 325/60-18s on mine with a wheel that has about 4.5" backspacing and had to do trimming and probably gonna have to do more of a lift than just my 2.5" leveling. all in all i love the stance of my truck now but I am most likely gonna need more lift but the backspacing on mine could be my problem.