We drove a Tahoe LT-3 4WD and found the 5.3-liter is a good engine that moves the Tahoe well around town. It has enough grunt to tow up to 8200 pounds, but we would have preferred more than four gears in the transmission, especially when climbing some long mountain grades northwest of Phoenix. We liked the fact that we couldn't feel the transitions when the Active Fuel Management shut off or turned back on four cylinders as needed during highway cruising. The system even works in normal city driving, though the only way we could tell was to see the indicator lights change on the driver information panel on the dashboard.
We drove on regular gasoline, but a flexible-fuel version of the Vortec 5300 is available that operates on either gasoline or on E85 ethanol fuel. Note, however, that fuel economy suffers by as much as 25 percent when E85 is used. Both versions of the Vortec 5300 meet GM's 200,000-mile durability requirements. With four-wheel drive, the 5.3-liter V8 is EPA-rated at 14 mpg in the City, 19 mpg on the Highway.
We drove the Hybrid model and found the two-mode hybrid system worked seamlessly. The system uses two electric motors in GM's new Electrically Variable Transmission (EVT) that has four fixed gears. The EVT is mated to a 6.0-liter V8 that also has Active Fuel Management. Total output is 332 horsepower and 367 pound-feet of torque. One of the motors aids power at low speeds and the other lends a hand at highway speeds. Under light throttle, the electric motor can propel the Tahoe up to 30 mph. With heavier throttle, the gasoline engine starts up smoothly, with only a little shudder. Like other systems, the gasoline engine turns off at stoplights and restarts as soon as it's needed.
The Hybrid's fuel economy makes the almost three-ton Tahoe as fuel efficient as a typical sedan. With 2WD, the Tahoe Hybrid is EPA-rated at 21 mpg in the City and 22 on the Highway. With 4WD, it gets 20/20 mpg City/Highway. While the Hybrid has considerably less towing capacity at 6000 pounds with 4WD and 6200 pounds with 2WD, that's still enough for many towing needs. Next Page