should I change gears or tranny???

done some digging now that it's light outside. According to a data plate for lack of better words in the glovebox the rear gears are 4.10:1, the tire size is LT235/85R16. I'm quite sure its known that its a Dana 60 being the truck is 3/4 ton. And it's 2WD not 4WD, forgot to add that.

I forgot to mention, any chance you can just up the tire size somewhat?

235-85-16 is really about as tall as he can go without going to a more agressive tread. to go taller, he would be pretty limited to 32's and bigger as far as availability is concerned. They make them. Theyre just hard as hell to find.