Why are tractor-trailer rig so much more fuel efficient

[slowmover]

". . Hard to believe, but less than 30 years ago a company like Ryder wasn't just spec'ing out trucks, but having exclusive models manufactured for it. Such was the case with the 20 futuristic Paymaster tractors built for Ryder in the early '70s. The Paymaster was invented by Dean Hobbensiefken of Lyons, OR; Ryder claimed the patents in 1974. The design boasted an aerodynamic profile and unique placement of the engine behind the cab. Ryder recently donated a renovated vintage '73 Paymaster to the American Truck Historical Society, for display at the National Automobile and Truck Museum in Auburn, IN."

The pioneering Paymaster truck on Biglorryblog. That's a wedge that works! - Biglorryblog


Back to the future | Overdrive - Owner Operators Trucking Magazine


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[t vago]

Originally Posted by Gregte

Another advantage big trucks have over our American cars is that the diesel engine is more efficient in producing power than the gasoline engine. this is due to the higher compression ratio that a diesel can and does run at.

Don't forget that semi diesels are turbocharged, too. This effectively gives them variable compression.

You will also notice that semis tend to have driving habits that somewhat resemble hypermiling, but it is mainly due to their having to move up to 40 tons of tractor and semi trailer.