I have a 1998 Chevrolet 2500HD with a 5.7L and a 5 speed transmission that has 347,000 miles on it. (Yes, I said 300) and the only thing major that has ever been done to the truck was a clutch job at about 150,000 miles and the intake gaskets have been changed three times now. This truck is a daily hauler in the fabrication business and is worked plenty and plenty hard, sometimes pulling a gooseneck trailer with about 10,000 lbs. on it. One great truck.