2008 GMC Yukon Hybrid

2-Mode Hybrid Power

Sales of the GMC Yukon Hybrid and its Chevrolet Tahoe cousin begin late in 2007. Equipped with a small-block 6.0-liter V-8 engine, each provides the expected benefits of a full-size truck, including towing up to 6,000 pounds. Running on unleaded fuel, the V-8 produces 332 horsepower and 367 pound-feet of torque.


Traditional full-hybrid systems have a single electric mode, used during low-speed and light-load driving. The 2-Mode system has one mode for city driving and another for highway operation. In low-speed mode, the vehicle operates with electric power alone, the gasoline engine alone, or a combination of the two. When operating on electricity alone, the gas engine is shut off, obviously boosting fuel economy enormously.


When operating in the second mode, the gasoline engine gets electric assist. Coupled with Active Fuel Management and other fuel-saving technologies, this lets the vehicle function with a smaller electric motor than would be required in a "one-mode" hybrid system. For passing, climbing a steep grade, or towing, the Yukon Hybrid runs on all eight cylinders.


Various vehicle components have been modified aerodynamically, to compensate for the added weight of the hybrid propulsion system, and the front end sits 10 millimeters lower than usual. The Yukon Hybrid gets a new grille, front/rear fascias, and streamlined hood. Rated a half-ton, the GMC Yukon Hybrid comes with either two- or four-wheel drive. Aluminum Ultra Bright wheels hold 18-inch tires. The antilock braking system incorporates regenerative capability, extracting energy from the wheels as they slow down and sending it into the battery pack for later use. Unlike most hybrid vehicles, which use a continuously variable transmission (CVT) with belts or bands, the Yukon and its Tahoe counterpart have a conventional Hydra-Matic.

Interior and Driving Dynamics

Like other hybrid vehicles on the market, this Yukon does exactly what's claimed by GMC, and does it adeptly. Apart from the auto-stop action, the Hybrid drives just like any Yukon—or similar Chevrolet Tahoe—as redesigned for the 2007 model year. More refined than its predecessors, the current Yukon yields a satisfying ride for a big SUV.