2008 Mercury Mariner Hybrid

Higher Fuel Economy Without Compromises

The Mercury Mariner Hybrid is just as practical and versatile as any compact SUV, but it gets superior fuel economy.

Performance

Hybrids often get knocked for not delivering fuel economy as advertised. That is not the case with the Mercury Mariner Hybrid. By combining power from a 133-horsepower four-cylinder gasoline engine and Continuously Variable Transmission (CVT) with a 94-horsepower electric motor, it provides a pleasant mix of both fuel economy and performance. Essentially, you get the performance of a larger V6 engine with fuel economy on par or better than a conventional four cylinder’s. Acceleration at lower speeds is brisk because the electric drive delivers all of its torque from a dead stop.

Fuel economy is what defines a hybrid, and after 12,000 miles behind the wheel of a long-term Mariner Hybrid test vehicle, we can say that drivers should easily achieve the EPA estimates of 28 mpg city/27 mpg highway. (Note that EPA estimates have dropped for all 2008 vehicles as the agency’s test methods for fuel economy now better reflect real-world driving.)

The big variable with fuel economy is driving style. If you are hard on the accelerator all the time, mileage will suffer. But drivers can fine tune a light-footed driving style by heeding information from the fuel computer to achieve fuel economy even higher than the EPA’s numbers. We’ve recorded in-town mileage of more than 35 miles per gallon and 30 miles per gallon on the highway just by working the electric drive motor as much as possible — this requires judicious acceleration from a standstill and while cruising. Our worst average per tank of fuel was 25 mpg, and that was during winter driving with lower than the recommend tire pressure.

Making the steering system electric, rather than using a traditional hydraulic system, is one of the many things that allows the Mercury Mariner Hybrid to run only on electric power at certain speeds; it also reduces the strain on the gasoline engine when it’s running. On a normal vehicle with hydraulic steering, the power-steering assist cuts out as soon as the engine is off because it’s tied to the gasoline engine. But electric power steering works all the time, even when the combustion engine is shut down and the Mariner Hybrid is being powered by the electric motor exclusively. Other hybrids use this technology, too.

Steering feel through the electrically assisted power steering system is surprisingly good. It’s a light touch that enhances the Mariner Hybrid’s nimble handling and fun-to-drive factor.

The hybrid system houses a 330-volt battery pack of 250 D-size nickel-metal-hydride cells beneath the rear cargo floor. The additional weight in the rear offsets the front engine and transmission mass for better weight distribution front to back. The result is a very balanced feel through turns and transitions on the highway.

Traction is also quite good, thanks to the standard all-wheel-drive system. The Mariner Hybrid manages rain-slick roads and winter snow and ice conditions with sure-footed confidence.

Ride quality is fine, but the low roll-resistance tires do translate a touch more road noise and harshness than regular all-season tires.

The Mercury Mariner Hybrid is a well-rounded package, that delivers on the hybrid promise of improved fuel economy with few compromises in a sensible SUV.