It's likely a stretch to think of a full-size sport-utility vehicle as green, but improving the gas mileage of these behemoths can have a big impact.

That's why Ford is shrinking the engine of its largest SUV.

MORE: 2014 Pickup Truck Gas Mileage: Ford vs Chevy vs Ram, Who's Best?

The 2015 Ford Expedition will be offered with the 3.5-liter EcoBoost V-6 currently used in the F-150 full-size pickup truck.

2015 Ford Expedition

2015 Ford Expedition

In fact, that will be the only engine offered on the Expedition in North America.

The twin-turbocharged, direct-injected EcoBoost engine will be paired with a six-speed automatic transmission with manual shifting mode.

EcoBoost arrives

Ford did not provide specific numbers, but it did say the EcoBoost will be more powerful than the current Expedition's naturally-aspirated 5.4-liter V-8 and--not surprisingly--more fuel-efficient.

The turbocharged V-6 produces 365 horsepower and 420 pound-feet of torque in the 2014 F-150; Ford's large pickup truck will also be replacedby a redesigned model for 2015. That's more than the 310 hp and 365 lb-ft of torque the 2014 Expedition's V-8 can muster.

MORE: Why Green Car Reports Writes About Full-Size Pickup Trucks

As for fuel economy, the current Expedition is rated at 16 mpg combined (14 mpg city, 20 mpg highway) for two-wheel drive models and 15 mpg combined (13 mpg city, 18 mpg highway) for four-wheel drive.

So there's plenty of room for improvement.

2015 Ford Expedition

2015 Ford Expedition

Other tech updates

Other mechanical updates include electric power steering--which Ford says will further improve fuel efficiency--and a new suspension system with adaptive damping.

The system uses sensors that can detect up to 46 distinct body, steering, and brake inputs to keep big SUV's girth in check.

There's more technology on the inside, including Ford's ubiquitous Sync with MyFord Touch system, displayed on a new 8-inch center-stack screen. Two 4.2-inch screens flank the speedometer in the gauge cluster.

The 2015 Expedition also received a minor exterior refresh, with a reshaped front end, optional LED fog lights, and available 22-inch wheels that probably won't be the hyper-miler's first choice.

Topping the 2015 Expedition range is a new Platinum model; other trim levels include XLT, Limited, and King Ranch.

Pricing and fuel economy figures will be released closer to the on-sale date of the giant seven-seat SUV--which, for the record, is 18 and a half feet long in its largest version.


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