2006 Jeep Liberty Review

The available 2.8-liter turbo-diesel four-cylinder engine is surprisingly satisfying, combining the horsepower of a small gasoline V6 with the torque of a V8 and the mileage of a four-cylinder. The diesel is rated at 160 horsepower and 295 pound-feet of torque. The EPA says the diesel should get 21/26 mpg city/highway. During a week of testing, we averaged about 21 mpg, including a fair amount of time spent off-road in low range. On the highway, the diesel Liberty becomes an easy cruiser, showing just 2000 rpm on the tach at 70 mph. Our highway mileage was close to 24 mpg, some 30 percent better than the 18 mpg we saw with the gas V6. And, just like the V6, the diesel is rated to tow up to 5000 pounds with the optional hitch.

Best of all, the new diesel seems to suffer few of the tradeoffs associated with oil-burning engines of the past. There is practically no smoke, and very little noise or vibration. This is largely thanks to the new common-rail technology developed in Europe, which uses a high-pressure fuel injection system that burns diesel fuel much more cleanly than earlier designs. There is no warm-up period before starting, because the glowplugs are electronicaly controlled. The turbocharger is an advanced design with variable-geometry vanes that deliver significant induction improvements at both low rpm and high rpm, and at high altitudes.

The diesel comes standard with a stronger five-speed electronic automatic transmission, which benefits from advanced logic. Depending on throttle input,this transmission can deliver two separate second-gear ratios, a lower ratio for quicker acceleration, a taller one for smooth downshifts.

The Liberty doesn't ride as smoothly on the road as a Ford Escape, particularly over bumps and other irregularities where it bobbles a bit. Nor does it handle as well as the more car-like SUVs. Steering effort is relatively easy at low speeds for a 4x4, nice when parking. On the road, the steering is reasonably solid on-center, a benefit of its power-assisted rack-and-pinion design. But the long-travel off-road suspension, set up to absorb impact without being overly harsh, makes for lethargic transient response in lane-change maneuvers. That said, the Liberty rides reasonably well for a short-wheelbase 4x4. It doesn't beat the driver up as much as a Jeep Wrangler does. The wider tires that are standard on Limited and optional on Renegade seem to offer more stability than the narrower tires of the Sport. The Liberty handled winding Virginia backroads well and felt fine on crowded freeways around Los Angeles.

The electronic stability program that comes on Liberty models can help the driver avoid accidents. ESP is especially valuable when driving on mixed surface conditions such as patchy snow, ice or gravel. If there's a discernible difference between what the driver asks through the steering and the vehicle's path, ESP applies selective braking and throttle input to put the Jeep back onto the driver's intended path. The system is calibrated to offer more control of the vehicle under a variety of conditions, and to operate in a manner that is not intrusive in normal or spirited driving.

We've also found the Liberty capable of handling fairly gnarly trails. It tackled steep ditches and gullies on an off-road trail, thanks to its short front and rear overhangs and a suspension that articulates well. We appreciated its tight turning radius while weaving through a stand of tightly spaced trees. We clambered over big rocks and fallen trees and slowly forded boulder-strewn creeks with 18 inches of rushing water. Jeep says Liberty can handle 20 inches at 10 mph. Its tract