I'm buying a Govplanet HMMWV and looking at engine swaps. Naturally the Duramax seems like the best option but the conversion kits from three different suppliers run from 10,000 to 15,000 with out the motor/tranny etc. I think a good option would be a Chevy Crate 454 or 502. It comes in a kit with tranny and computer and has 50,000 mile warranty. More @Wikipedia
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