Maximum MPG
This perfect fuel mileage recipe comes from the results of past trucks competing in the Diesel Power Challenge. In the most recent contest, the Duramax picked up First, Second, and Third place finishes in the fuel economy portion of the competition. This is nothing new. In fact, it is the very same thing that happened in the first Diesel Power Challenge. The highest place Ford has ever reached in this event is Fourth.
We would start with an '06 Duramax-equipped 2500 HD regular cab, which we would outfit with a shortbed. The next modification would be an adjustable air spring suspension so our truck ride would be as low as possible when on the highway. We would rely more on water injection for cooling, so our grille opening could be smaller for better aerodynamics. Fiberglass, carbon fiber, Lexan, and aluminum would be used in place of steel and glass wherever practical. The rear AAM 11 -inch rear axle would get the highest gears possible (3.42). EFILive would help tune our engine for maximum fuel efficiency. Alternative fuels such as CNG, propane, and hydrogen would all be added to the Duramax through electronic controllers tied into the main engine computer. Our goal would be 50 mpg.
Truck: '06 Chevy 2500 HD standard cab, two-wheel drive
Engine: 6.6L Duramax
Performance modifications: Water injection, CNG and propane fumigation, a hydrogen-on-demand system powered by a driveshaft alternator and two batteries, and EFILive tuning
Estimated HP: 300 hp
Transmission: ZF six-speed
Rear Axle: AAM 1150 with 3.42 gearing
Suspension: Adjustable air shocks
Tires: Low-rolling resistance Michelin X radials
Wheels: Light aluminum
Chassis modifications: Shortbed
Body Modifications: Fiberglass, carbon fiber, aluminum, and Lexan replacing glass and steel
Why it will work: Lightweight, two-wheel drive, highly geared, EFILive tuning, CNG, propane, and hydrogen