Trends: Fuel-Efficient Pickups

Fuel economy has climbed from tenth to third place among priorities of new pickup buyers, after durability and value. That’s important, because there are a lot of pickup buyers out there and these highly functional vehicles are going to be used for business and personal use for some time.

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.

XFE models are powered by GM’s 5.3 liter V-8 engine and are flexible-fuel vehicles capable of running on gasoline or E85 ethanol. The Hydra-Matic 6L80 six-speed automatic transmission used has a wide overall ratio spread of 6.04:1 for a ‘steep’ first gear and very ‘tall’ fifth and sixth overdrive gears for quiet, low-rpm highway cruising. This maximizes both acceleration and highway fuel economy. Finally, a rear axle with automatic locking rear differential and fuel-saving 3.08:1 ratio gearing is standard.

Ford’s SFE 4.6-liter, 3-valve Triton V-8, which is optimized for better performance with improved horsepower and torque, is also a flexible-fuel vehicle. It uses open valve injection for improved air/fuel flow into the combustion chambers, allowing greater spark advance at higher loads and engine speeds. This delivers increased horsepower during towing and higher rpm operation, lower emissions, and more efficient use of fuel.

The SFE also regulates fuel consumption by using aggressive deceleration fuel shut-off that temporarily turns off fuel delivery when the accelerator pedal is released. Flow seamlessly resumes when low speeds are reached or a driver accelerates. Ford uses software to prevent the engine hesitation that’s normally associated with fuel interruption.

Part of the new SFE package is a new fuel-efficient automatic transmission and a 3.15:1 rear axle. The six-speed automatic offers a wider gear ratio span for improved responsiveness in low gears and better fuel economy in the taller gears.

GM’s vehicles went on a diet starting with a weight-reducing aluminum cylinder block and heads. Lighter weight aluminum wheels, including the spare, are installed and aluminum lower control arms are used. The Ford F-150 has also gone through some lightweighting with a fully boxed frame constructed with hydro-formed and high strength steel side rails. Lightweight, ultra-high-strength steel lightens the truck by up to 100 pounds compared to the previous F-150. The lightweight frame also provides 10 percent more torsional rigidity for increased durability and safety.

GM says there’s a 5 percent increase in EPA estimated highway fuel economy and over 7 percent improved mileage in city driving. The result is 15 city and 21 highway mileage EPA ratings. Ford’s SFE pickups turn in 15 mpg in city driving and 21 mpg on the highway. While 5 percent – or about one mpg – might not seem that much, it does add up and can make a difference of several hundred dollars in gas costs annually, depending on the cost of gasoline.

The XFE package is offered in the LT trim for the Chevrolet Silverado and LS and LT trims for the Chevrolet Tahoe. The GMC Sierra XFE comes with SLE trim and the GMC Yukon XFE is offered with SLE and SLT trim. The SFE package can be ordered on F-150 SuperCrew XL and XLT models with 5.5-foot beds. Both XFE and SFE packages are available on 4x2 models.