The Ram 1500 EcoDiesel is currently the most fuel-efficient full-size pickup truck on sale in the U.S., but Ram plans to improve on that performance.

Well, it plans to improve the ratings by 1 mpg, anyway.

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The 2015 Ram 1500 EcoDiesel HFE--for High Fuel Efficiency, of course--increases the 3.0-liter turbodiesel V-6 Ram's fuel-economy advantage over rival full-size trucks, but only by a little.

Ram says the new model will return 24 mpg combined (21 mpg city, 29 mpg highway). That's a 1-mpg improvement in each of the three categories over the standard rear-wheel drive EcoDiesel.

2015 Ram 1500 EcoDiesel HFE

2015 Ram 1500 EcoDiesel HFE

While the EcoDiesel engine is also available with four-wheel drive in other trim levels, the HFE is rear-wheel drive only. The diesel engine is paired with an eight-speed automatic transmission in all models.

The HFE is also limited to a single body configuration--a four-door crew cab with the 6-foot-4-inch bed from the base Ram 1500 Tradesman model.

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It also gets a body-color front fascia and and HFE badge that "heralds its mpg claims," according to Ram.

Imagine a world where pickup owners brag as much about fuel economy as they do about tow ratings and horsepower!

2015 Ram 1500 EcoDiesel HFE

2015 Ram 1500 EcoDiesel HFE

The 3.0-liter turbocharged V-6 appears unchanged, meaning it should produce the same 240 horsepower and 420 pound-feet of torque it does in other models.

The EcoDiesel HFE joins an existing HFE model offered with the 3.6-liter Pentastar V-6. That version is rated at 21 mpg combined (18 mpg city, 25 mpg highway).

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Both HFE models also include the same fuel-saving features that are standard across the Ram 1500 range, including active grille shutters, aerodynamic under-body panels, and an engine start-stop system.

The 2015 Ram 1500 EcoDiesel HFE goes on sale in "late first quarter" 2015. Pricing will be announced closer to that date.


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