visible difference between 5.3 and 4.8
Thanks
4.8 has a different crankshaft, longer rods and flattop pistons, whereas earlier Gen III 5.3L's had dished pistons. Newer Gen IV style 5.3L's with the 243/799 casting heads have flattops now.
stroke for the 4.8L is 83mm (3.268˝)
stroke for the 53L is 92mm (3.622˝)
so if you measure less than 3.5" you have a 4.8L, more than 3.5" you have a 5.3L





