What is it?
General Motors promises that its upcoming hybrid versions of the large Chevrolet Tahoe and GMC Yukon SUVs will provide a 25-percent fuel economy improvement. Unlike in earlier GM hybrid pickups, these models use a full-hybrid system, similar to that used by Toyota. This allows the vehicle to operate on electric power, gasoline power, or a combination of the two, depending on the driving conditions. The system uses two compact electric motors and a battery mounted just ahead of the rear wheels to assist the conventional gasoline engine. It's designed for use with both gasoline and diesel engines. The models also use GM's cylinder-deactivation system, which automatically cuts out half of the engine's cylinders when they're not needed, such as while cruising on the highway. Pricing has not been announced.
CR's take:
In our tests of the Chevrolet Tahoe with a 5.3-liter V8 (test available to subscribers only), we got only 13 mpg overall in our real-world fuel-economy tests. If GM's claims are accurate, the hybrid powertrain could boost gas mileage to about 16 mpg. This is still not great, but is better than in any other large SUV we've tested.
What's new or notable?
GM's new full-hybrid system will use a "two-mode" design that was developed with Daimler-Chrysler and BMW and is said to offer increased gas mileage both around town and at highway speeds.
