It's taken a long time to arrive, but Ford's fuel-efficient 2.0-liter EcoBoost four-cylinder engine is now available as an option on both the 2012 Ford Explorer and the 2012 Ford Edge crossover utility.

It's the first time any Ford Explorer has been offered with a four in the model's 22-year history; previously, the mid-size sport-utility vehicle was offered with a variety of V-6s and even a V-8.

The Ford Edge, similarly, has had only V-6 engines since its launch as a 2007 model. The EcoBoost model was unveiled way back in February 2010, but is finally on sale for the 2012 model year.

2012 Ford Edge

2012 Ford Edge

The 2012 Explorer with EcoBoost is rated at 20 mpg city, 28 mpg highway, for an estimated 23-mpg combined rating. The smaller, lighter 2012 Edge with EcoBoost comes in at 21 mpg city, 30 mpg highway, for a likely combined rating around 24 mpg.

The EcoBoost four in both vehicles is direct-injected and turbocharged, allowing it to produce 240 horsepower (and a whopping 270 pounds-feet of torque) from its 2.0 liters. That's only 45 or 50 hp less than the 3.5-liter V-6 engine used in the Edge and Explorer, respectively.

Ford's EcoBoost four is new to the States for the 2012 model year, but it's been offered in Europe for a year now--and more of the fuel-efficient engines are on the way, including a 1.0-liter three-cylinder EcoBoost option for a future Ford Fiesta likely to be sold in the U.S.

Ford has said it will offer an EcoBoost option on 90 percent of its vehicle lines by 2013. It's been especially popular in the F-150 pickup truck line, which now sells more V-6 models (both regular and EcoBoost) than V-8 versions.

2011 Ford F-150 EcoBoost rear view - Drive Tour 2011

2011 Ford F-150 EcoBoost rear view - Drive Tour 2011

But back to family haulers. If you're considering the EcoBoost option for either the Explorer or the Edge, you should ask yourself these questions:

- How much do I need to tow?

The 2012 Explorer with EcoBoost has a rated towing capacity of 2000 pounds; with the most powerful V-6, that goes up to 5000 pounds. Similarly, the EcoBoost Edge can tow 1500  pounds, but its more powerful V-6 model can tow 3500 pounds.

You should also think hard about what you're likely to tow regularly. Buying a thirstier vehicle because you might, one day, have to tow a boat or trailer that you don't own could be an expensive way to plan for an unlikely occurence. But only you can answer that.

- Do you plan to go off-road?

The Edge is largely a suburban crossover, but the Explorer has more off-road capabilities--despite having moved to unitary construction from its previous truck-style body-on-frame design.

Ford strongly suggests the 3.5-liter V-6 for serious off-roaders, because the EcoBoost option comes only with front-wheel drive. If you want all-wheel drive, you have to get the V-6.

We question how many Edges and Explorers will ever see duty more serious than muddy playing fields and slippery suburban roads, but again, you're buying the car; you know how you plan to use it.

- Is there a payback on the cost--and if not, do I care?

Depending on your annual mileage, local gas prices, and what you predict gas will cost in a few years, the $995 cost of the EcoBoost engine may not pay back in gas-cost savings.

But that isn't necessarily a reason to avoid the option. It's possible that EcoBoost-equipped Explorers and Edges will be worth more as used cars than those with thirstier engines, especially if gas prices rise.

This one's entirely your call.



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