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Both General Motors and Ford have new 2009 models to meet this shift in priorities. GM offers its XFE (Xtra Fuel Economy) versions of the Chevrolet Silverado, GMC Sierra, Chevrolet Tahoe and GMC Yukon. At Ford, it’s the SFE (superior fuel economy) package for F-150 pickups. Both achieve improved fuel economy via better aerodynamics, more efficient drivetrains and reduced weight. GM and Ford also use low rolling resistant tires.

The Silverado XFE and Sierra XFE models’ 0.412 coefficient of drag – great for pickups – is achieved with a soft tonneau cover, extended front lower air dam, lowered suspension, and revised chassis tuning. The latter two are also used on the Tahoe XFE and Yukon XFE for an excellent drag coefficient for full-size SUVs of 0.349.

The new Ford F-150 SuperCrew 4x2 with 5.5-foot box has a coefficient of drag of 0.403, 6 percent better than a comparable 2008 F-150. Improvements include a new chamfered shape to the rear of the cab , which is incorporated into the center-high-mount stop lamp to help direct the aerodynamic wake over the pickup box more efficiently. A tailgate top also angles outward to create a bold lip with a wider surface at the top, working with the cab chamfering to efficiently direct airflow over the box. An improved front bumper valence and spoiler better manage airflow underneath the truck.
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"more efficient drivetrains"