Actually, mileage isn't too bad. It gets 15 in town, 17-18 on the highway (loaded, with A/C and 5 people). The Gen 5 big blocks make tons more power with a few small mods and a good tune. I did Cam, heads, exhaust, intake, and Accel DFI. It bangs out decent mileage on 87 octane too. Its the "7000lb factor" that holds it back. It does some bitchin burnouts too.