Rear End Troubles! AGAIN
 

So in January I hopped in my truck and was about to drive to school. Until It felt like only one tires was spinning, which it was. Had it towed to a shop and the ripped the rear end apart, said it was a c-clip or something? I'm not a technician so I don't know much. That got fixed and the truck has been sitting in my garage since to keep it from the harsh Maine Winter. I started it a few weeks ago to move it and wash it down and the battery quit on me. My uncle's 6.6l turbo diesel couldn't even jump it. So it sat for about three weeks until I got a new battery. Now my rear end it froze up again! Mechanic said he doubts it's the axle again. Maybe the brake drum is ****ed? I'd really like to do the work myself. I'm not looking to do a whole fix I just need to drive it 20 yards back into the garage.

Jack up the rear and try moving the wheels back and forth and listen for any sounds or resistance that might give you an ideal. You can remove the wheels and check the brakes. If brakes OK remove the differential cover (drain the oil) and check what's locked up.