What's wrong with 3.90's ? I think that's an excellent choice. Beats the heck out of the stock 4.57's, at least for seeing some highway duty. If it's just going to be beating around the property, than just leave the stock gears in.
Just be glad you don't have 6.13's !
3500 RPM at 63 mph with 37" tall tires.
If you know what tires you'll be running, go to this
site . That should help clear up your decision.
Good Luck Phil, whatever you decide
.
