With a bit of a offset wheel I ran 35-12.5/20 on my 2010 with no rubbing Had the factory mud flaps though not big ones
I think a -12 offset With the 12.5 wide tires they were about 1" outside the factory fender flares
I run 35x12.5x20 toyo at 2's on 20x9 +18 offset rims in the summer and they rub on the mudflaps at full lock with a 2.5" carli leveling kit but many ppl run 35's on stock trucks with factory wheels
305 for sure on stock suspension. you can go to 325 if you do a leveling kit but you will have mudflap rubbing at full turn. I have run both sizes on my 2008 and dad has done the same on his 2012.