It depends on what you do with your truck. Wheel bearings need regreasing if you go through water much. Diff fluid should be changed more often if you offroad. You have an '08 so I don't know as much about their weaknesses. Some of the earlier next-gens have problems with the diffs grenading, but I think I read they changed some areas there so you're probably safe. If you offroad you might also want to consider some skid plates for the front diff as it's aluminum and prone to damage, the rear diff plate can peal back, but if you're a good driver you should be putting your tires over the rocks and not your diff. Other than that, some good AT or MT's and we always recommend rock sliders as an early mod to those who offroad.
Enjoy.