Our 2008 Technology of the Year just got more work duty.

GMC has unveiled its Two-Mode 2009 Sierra Hybrid at the Chicago Auto Show.

As one of the first GM trucks equipped with the Two-Mode system (the hybrid technology also appears in 2008 GMC Yukon and Chevy Tahoe hybrids), GMC says the Sierra Hybrid achieves 40 percent greater city fuel economy and a 25 percent improvement in overall fuel economy when compared to the standard Sierra, which gets an EPA-rated 13 mpg city and 18 mpg highway. The hybrid version can reach speeds up to 30 mph on electric power and features additional fuel-saving technology, such as a 6.0-liter V-8 with electronic variable transmission (EVT) and GM's active fuel management.

Similar to its Two-Mode SUV cousins, the Sierra Hybrid has a 6100-pound towing capacity, is available in two- or four-wheel drive (StabiliTrak and a locking rear axle are standard) and benefits from subtle body enhancements - a slightly deeper front air dam and a tonneau cover to reduce air drag.

Inside the truck, drivers will notice a new instrument cluster and a battery pack located under the rear seat.

The Sierra Hybrid should be in showrooms by Fall 2008.

Click below for high-resolution Sierra Hybrid images.