The engine types may include 4.3L 262Cu. V6 GAS OHV Naturally Aspirated,4.8L 294Cu. V8 GAS OHV Natura lly Aspirated,5.3L 5328CC 325Cu. V8 FLEX OHV Naturally Aspirated,5.3L 5328CC 325Cu. V8 FULL HYBRID EV-GAS (FHEV) OHV Natur ally Aspirated,5.3L 5328CC 325Cu.