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Windows
WARNING Leaving children, helpless adults, or pets in a vehicle with the windows closed is dangerous. They can be overcome by the extreme heat and suffer permanent injuries or even death from hea ...

New for 2011
The Sierra Hybrid gets GM's OnStar 9.0 telematics system that GM says provides better voice recognition. GM also said they have worked to cut down on the amount of wind noise occupants hear. ...

Under the Hood
The Yukon Hybrid uses a two-mode hybrid system. The system augments the SUV's V-8 engine with two electric motors, both powered by a 300-volt battery pack. A cylinder-deactivation system cuts powe ...