My C7 Cat required more costly maintenance than my 2012 diesel F350 because it took twice as much oil engine and transmission, more expensive oil and fuel filters, air brake filters, antifreeze, wheel bearing maintenance, more grease as well as two Allison transmission filters. Also the transmission and engines I used synthetic oils. Transynd oil is very expensive and requires a more frequent change interval. The synthetic engine oil is expensive as well. Gas engines are much cheaper to maintain if you follow the mfg's manual. And don't forget the cost of DEF :-)
