My neighbour has a 2009 F350 CC 4x4 with 20in rims. What is the largest tire he can put on her without rubbing. He has the stock 20in rims, no lift.

 

I'm running 35x12.50R22 now. Had to tie back the fender liner a bit though. But no issues rubbing.

 

no experience yet with this.. but i've been reading a lot of threads lately.. here and other forums.. most guys seem to be getting away with 35x12.5x20's... but they rub at full steering lock.. rubs on the radius arms.. not a big deal to me.. but i'm about to put on a 3.5" leveling kit and 37x13.5x20.. and i know it will rub on the radius arms.. maybe someone else can chime in that has 35's..

 

Your wheel offset is what's really going to determine if you rub or not when youre running 35-37" tires with or without a lift/leveling kit. The best thing I did, was chat with the guys at discount tire and other tire shops. They'll tell you what your offset needs to be. I've got toyo M/T 35x12.50R22 on 22x9.50 w/20 offset. I can turn 100% without any rub except the wheel well panel. Easy fix though, just trim or pull back with zip Ties or they make wheel well brackets that pull them back.