If it helps I've got an '05…
If it helps I've got an '05 Silverado 4x4 with a 4.8 and it about to roll over 307000 miles runs like a top motor transmission and rear end.. I haven't had to do anything major to motor.. I have a pan gasket slow leak other than that no motor issues .. And none with transmission or rear end.. The front end suspension has given me the most issues although I call that regular maintenance due to the type of work that I do... I've definitely gotten my money's with out of this truck.. Good luck. If it were me I'd probably go for it...