The diffs are professionally setup. I have solid pinion spacers, oil slingers. The gears are not but the bearings and races are heat treated. The gear sets are Yukon. Welded rear and a Detroit truetrac in the front. The rig is a 89 reg cab with a custom tube box. 3" body lift, 5" spring lift, 6" shackles. 36" Irocs. drivetrain Gm 350 TBI 700r4 Toyota case 4.7 low gears.
I think that's your answer.... start looking for 1tons.
