2002 Sport Trac 4x4-max tire size?

[4x4Trac]

I have a 2002 Sport Trac 4x4 with no modifications or lift. It came with 255/70r16's and I want to put the largest BFGoodrich A/T's on it. I don't want to lift it at this time or change out the rims. What is the largest tire size I can put on it? Does anyone know if the 32x11.5 BFG's will fit? If not, how about 31x10.5?

Thank you.

 

[pistolPJ]

we have about the same truck and it swallowed my old 31x10.50-15 BFG MT's, and all i did was a 1.25 inch TT/shackle lift and i easily fit the 32 BFG ATs with the only rubbing being in reverse.