Smaller engines, turbo-charging, and lighter weight add up to big fuel economy gains, even without a hybrid system.

There was a time when automakers could meet fuel efficiency standards by shifting to smaller cars. No longer. Thanks to the so-called “footprint formula” used to establish higher fuel efficiency standards, automakers will need to make big gains in all segments in order to meet tougher efficiency levels starting in 2012. That’s why small cars like the gas-powered Honda Fit, which is rated at 35 MPG on the highway, might be offered as the Honda Fit Hybrid to push the MPG even higher. At the same time, full-line carmakers, using every efficiency trick in the book, will make their larger vehicles go further on a gallon of gas.

Case in point: The next-generation Ford Explorer, once the poster child for SUV-obsessed America, will move to a car-like unibody construction and add an EcoBoost turbocharged four-cylinder engine and six-speed automatic transmission as its standard powertrain. As a result, the 2011 Ford Explorer should turn in combined highway-city fuel economy above 20 MPG.

Creativity is the key to improving efficiency. Ford has gone through the entire vehicle and put it on a weight-reduction program, using lightweight steel, aluminum and composites to drop weight—and thus maintained its heavier predecessor’s performance with a smaller powerplant.

Other factors boosting the fuel economy are twin independent variable camshaft timing, electric power-assisted steering, advanced battery management, fast engine warm-up and aggressive deceleration fuel shutoff. The Explorer also features Ford’s first U.S.-application of a variable-displacement air conditioning compressor that reduces parasitic engine drag.
This year’s 4.0-liter V6 Explorer is EPA-rated at 14 MPG city and 20 MPG on the highway. A 30 percent improvement would mean the 2011 2.0-liter EcoBoost model should deliver about 18 MPG in the city and 26 MPG on the highway. The EPA has not yet certified official fuel economy numbers.

Big Sellers Matter

The current Explorer’s seven-passenger capacity and towing abilities are expected to be maintained in the new models. Before you start thinking the Explorer’s off-road capabilities might be compromised by the move to unibody construction, note that the Jeep Grand Cherokee—which has impeccable off-road credentials—has featured a similar structure throughout its modern life.

Does this news have anything to do with hybrids? No. But hybrid fans should recognize the importance of fuel use reduction across the entire U.S. lineup. The Explorer for years had a place in the top 10 best-selling vehicles in the U.S., selling almost 3 million units in its first seven years on the market (1991-1997). This year the Explorer sold more than 31,000 units in the first half of the year, a boost of 30 percent compared to last year, but far off its heyday. It is currently the third best-selling Ford SUV, trailing the car-based Escape (which has a hybrid model) and Edge. All cars and trucks, with or without electric-drive, need to go on a diet. The Explorer’s 30 percent gain in fuel efficiency deserves praise.