Hi all, not to experienced on 4x4's....really just been around racing atv's, and motocross. Here my question is...my dad's tow rig is an 00' 4 door GMC Sierra 3500 4x4, 454, dually. It has a 14 bolt rear end...what gears is he running? 4:10's? what??? Me and him got in an argument and he swears he's got 4:10's...what do ya'll think it is?