This truck is a very unique build. It started life as a 1500 4x4 with a 350 engine but was expertly converted to a 454 with a 4L80E high performance 4-speed automatic transmission. It has been CARB certified and just easily passed smog. Other improvements are a 8000 lb. front winch, dual batteries, built in compressor under the hood, and a SONY stereo with backup camera. It runs and drives great with everything working. The mileage showing is believed to be the total miles on the truck with the mileage since the upgrades being much less.