So you just bought your first Ram Cummins truck, or you are the proud owner of the latest of many Ram trucks. Either way, there can be some confusion regarding the maintenance that should be performed to your Ram Cummins truck as a whole, and specifically, to your engine (5.9 or 6.7), automatic transmission (47re, 48re, 68rfe, Aisin AS68, Aisin AS69), manual transmission (Getrag, NV4500, NV5600, G56), differentials, brake system, power steering system, etc., to keep it running strong.