I have achieved an impressive 373,000 miles out of the engine with no rebuilding. (1996 Ford Explorer Eddie Bower 4x4, 4.0 OHV) of course the accessories are another thing. 4 Alternators, 2 water pumps 4 radiators, 1 radiator fan, 1 fuel pump, 1 front driveshaft, Ujoint set for front and back...