One problem related to differential unit has been reported for the 2008 Dodge Ram 2500. The most recently reported issues are listed below.
The heater works on occasion from Nov 13 till I replaced it in may 2015, now its August 2015 and the heater has completely stopped working. I live in alaska and a heater is a huge deal. Also during an oil change noticed the tie rod is all gooped with oil. Have an 09 1500 that the tie rod broke on. Curious if my 08 is gonna have the same issue. The rear differential is leaking oil all of a sudden as of June 2015 after hauling my 24 foot trailer 1200 miles. When I put the truck in 4 low and drive it makes a huge clucking sound doesn't turn very well either. It feels like my steering is about to go out. I can't drive up my driveway without digging wholes in the gravel. I bought the truck used November 2013 and feel like I got a lemon.