One problem related to differential unit has been reported for the 2003 Dodge Ram 2500. The most recently reported issues are listed below.
After vehicle was warmed up a clanking sound started. Also, when towing a fifth wheel trailer, after and after traveling 100 miles vehicle shook like the rear end was going to fall out. Dealer duplicated the problem , and stated it was either the rear end or the differential. Manufacturer offered no help. The consumer stated that the wrong lube in the rear end differential. Manufacturer advised a different lube. Consumer waiting for results when 5th wheel RV is being towed.