GM's first full hybrid is a massive SUV, revealing the company's efforts to revive the flagging SUV market. The Yukon Hybrid is designed to pull trailers and boats while hauling cargo and people, all while getting around 20 mpg.
The gas engine in the Yukon Hybrid is a 6-liter V-8. It uses cylinder deactivation, which can reduce it down to four cylinders, under certain low-load driving conditions. But the hybrid system, integrated through the transmission, gives the vehicle its excellent city mileage.