A lot of times what is thought of as a starter problem, is actually just a poor connection in the wiring.(usually at the battery) I have seen starters that get the drive gear stuck in the 'out' position get fixed by either a few solid taps with a BFH on the starter itself, or putting the manual transmission(if equipped) in gear and rocking the truck forward and backward. The rear main is a little bit of a messy(oily) job, but you can probably do it yourself in an afternoon.
