Our good friend Tom recommend Matt at American Gear in San Luis for any differential work. So last year I got Matt to regear the differentials from 4.10 to 4.56. This will let me run 31″ tires with the speedometer close to factory specs and give a little more power than she had before. For the rear I went with Eaton Truetrac and I left the front differential open. I just finished painting them with POR, now they are ready to go back in the truck.