Test Drive: Chevrolet Tahoe Hybrid saves gas in a big way

As gas prices climb past the $4-a-gallon mark, the interest in hybrid vehicles has increased significantly. Most of that interest is on compact and midsize hybrid cars, but Chevrolet's new Tahoe Hybrid sport utility vehicle attracted a lot of attention during a weeklong test

The Tahoe, and its General Motors corporate sibling, the GMC Yukon Hybrid, are the first full-size SUVs to offer hybrid powertrains. They come in both 2- and 4-wheel-drive models. Including destination charges and a long list of standard luxury features, the 2wd Tahoe Hybrid starts at $50,490 and the 4wd begins at $53,295. For the 4wd model, the Hybrid costs about $4,000 more than Tahoe LTZ 4x4 with the standard gasoline engine.

The Chevy and GMC SUVs share GM's new 2-Mode hybrid system, which has as a primary component an electrically variable transmission (EVT).

The EVT is like having two separate gearboxes -- one with continuously variable operation for light-duty driving, and another with normal fixed-gear operation for high-load conditions, such as highway driving or towing.

The EVT has two integrated electric motors, each with an output of 60 kilowatts. These motors can power the vehicle solely on electricity up to 25 to 30 mph, if the battery pack located beneath the rear seat has sufficient charge. Otherwise, the Tahoe will operate on a combination of the motors and a V-8 gasoline engine. The batteries recharge through regenerative braking and by using gas engine power.

The hybrid system works in combination with GM's newest generation 6.0-liter V-8. The engine deactivates half its cylinders when they are not needed. The Tahoe Hybrid delivers up to 332 horsepower and 367 ft-lbs. of torque, and the 4wd version has a towing capacity of 6,000 pounds.

The eight-passenger Tahoe proved flawless in operation, working as seamlessly as familiar hybrids, such as the Toyota Prius and Honda Civic. In such a large vehicle, it was unique to hear nothing more than the whirr of an electric motor at 25 mph.

Cutting wind resistance

The Tahoe/Yukon Hybrids feature special aerodynamic aids that help fuel mileage. The front fascia has no fog lamps and tow hook openings, while a lower front air dam redirects airflow to reduce turbulence and drag. The vehicle has no roof-rack side rails. The engineers modified the wheel openings and even tapered the running boards to cut wind resistance.

Chevrolet used a number of weight-saving steps with its hybrid SUVs. The vehicles have a lighter aluminum hood and tailgate. Low-rolling-resistance 18-inch tires are mounted on low-mass aluminum wheels. In addition, there is no spare tire or jack, so Chevy provides an air compressor and tire-sealant kit for small punctures.

CONTINUED 1 | 2 Next