Fuel Mileage Information on Semi Trucks

by Richard Rowe
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Though the average tractor trailer fuel mileage of between 7 to 8 miles per gallon (MPG) may not seem impressive, it's a vast improvement over older designs that rarely saw better than 2 to 3 MPG.


Turbocharging helps with gas mileage.

Turbocharging increases a truck's fuel economy by applying torque only when it's needed. Modern turbocharged trucks regularly get more than 2 MPG better than identical non-turbo trucks.

Front Aerodynamics

The more aerodynamic the truck the better.

The pointier the truck is, the better fuel economy it will get. A good example is the Kenworth T2000, whose long, pointed snout helps to increase its fuel economy.

Rear Aerodynamics

Trailers that are "boat-tailed" (tapered at the rear end) are known to increase fuel economy by as much as 10 percent over traditional "box" trailers.


New transmission have improved MPG.

The newest generation of automated manual transmissions consistently outperform manual transmissions of the same design, yielding an average 15 percent improvement in fuel economy.


Torque is required for travel through mountains.

Travel through very mountainous areas requires an engine which produces more torque for optimal mileage.