sentences:  This featured an Allison MT-643 automatic transmission, and a Detroit Diesel engine displacing 500 cubic inches (8.2 L).The original 11.00X20 Bias ply tires on split ring type rims were later changed fleet-wide to Michelin radials on bolt-together rims in 2002, due to safety concerns over the split rims.The M49 fuel tanker and M50 water tanker variants were initially based on the M44 chassis.