I am having differential issues with 2015 Ram 2500. Dealer replaced pinion and ring gear. The new gear was damaged and the technician welded on it and dressed it up some way and installed it. It makes a terrible rattling sound when coasting at about 25 mph. When starting off and turning either to left or right, especially up hill, it vibrates like you are running over rumble strips. This truck has 69,000 miles. What should the dealer do to correct this issue?