4. Though the 4.8L and 5.3L shared many of their components, the 4.8L was equipped with a different crank, rod and piston combination. The shorter stroke (3.267 vs. 3.622 ins.) combined with a longer rod and a flat-top piston to achieve a reasonable compression ratio with the reduced displacement. Note also we replaced the well-worn stock head gaskets with new Fel Pro MLS units.