I can clear 34x9.50s on my 2wd. I have a 6.5 inch lift and glass fendars. I had to cut some wheel houses and bang some fire walls. I run 33x10.50s right now no rubing and its a 2wd. so with a 4wd and 3 inches u should be able to. I can shou you pix of my wheel openings if you wanna see how much metal i cut. If you use wider wheels you can make your tires a lil shorter, because they flatten your foot print.check your wheels backspace too, so they will clear when you turn. On the rear you can prolly cut the rear in bed fendars off and make or weld some taller ones in. this will help u to not bottom out.
hope that helps
Brax