GMC sixes were designed to be rebuilt multiple times. The pickup and midsize truck engines benefited from the same design features as the big rig engines- - - - -some of those engines even had cylinder assemblies that were separate from the crankcase, such as the 503 cubic inch inline six used in the mid-1950's heavy duty trucks. For instance, GMV 228-302 connecting rods have full-floating wrist pin bushings and lock rings in the pistons to retain the pins- - - -Chevy uses a clamp bolt in the rod to lock the pin to the rod. GMC oil pumps are huge compared to Chevy pumps, and the GMC runs approximately twice as much oil pressure. GMC has a much better cylinder head design- - - - -and the list goes on and on!
Jerry
