Chevrolet launched its 2009 Silverado Hybrid in Los Angeles, but GMC waited to unveil its Sierra counterpart until today. The Sierra Hybrid, another application of GM's 2-Mode hybrid technology, makes its debut this week at the Chicago auto show.

Like its Chevy sibling, the Sierra Hybrid uses a 6.0-liter V-8 and electric motor coupled through the same two-mode transmission used in all of GM's full-size truck hybrids. GM claims the hybrid system helps the truck achieve a 25 percent improvement in overall fuel economy - a sizable gain, if true.

Although we won't know the actual EPA figures for the hybrid pickup until later this year, we do know the Sierra Hybrid will still be capable of towing close to 6100 pounds and a maximum payload of 1459 pounds. Look for it to arrive in GMC dealers this fall.

(Click through for a gallery of the Sierra Hybrid and a release from GM)

GM RELEASE

2009 SIERRA HYBRID DELIVERS 25-PERCENT IMPROVED FUEL ECONOMY WITH ALL OF GMC’S PROFESSIONAL GRADE CAPABILITY

CHICAGO – GMC announced the 2009 GMC Sierra Hybrid, a powerful full-size pickup that achieves 40-percent greater city fuel economy and a 25-percent improvement in overall fuel economy while delivering the capability expected of a full-size truck – including a 6,100-pound (2,767 kg) towing capacity.

Partnering General Motors’ patented two-mode hybrid system and a powerful 6.0L gas V-8, the Sierra Hybrid delivers highly efficient performance, including all-electric driving up to 30 mph (48 km/h). That allows fuel savings to be realized even when the truck is fully loaded or towing a trailer.

“The Sierra Hybrid represents GMC’s commitment to engineering excellence, delivering a fully functional truck that offers a significant improvement in fuel economy,