14 bolt 00' GMC?

[theitalian404]

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?

 

[89GMCSuburban]

Could be 3.73's or 4.10's. The only way to tell...look in the glove box and look for the axle code. Those are the RPO codes, they'll have three number or letter combinations. Write them all down, and go here and enter them in. It'll tell you the different options the truck came with...even some you may not even know about.