Is this a 5.3 or 4.8

[George C]

Looks like you know your stuff. I just looked up the PCM and its for a 2001-2002. The number on the PCM is 12200411. The guy I got the engine from told me it was out of a Tahoe but he is not sure of the year. Well the PCM at least narrows it down to either 2001 or 2002

there ya go. now i do believe in 02 they started to use MLS gaskets from factory. i think 01 still had graphite