GMC Graphyte Hybrid

The GMC Graphyte Hybrid is a concept sport utility vehicle built by GMC, the truck and utility marque of General Motors, and shown to the public at the 2005 Detroit auto show. It was a showcase for a two-mode hybrid drive that joins electric propulsion with a combustion engine, and the maker claimed it could save about a quarter of fuel at low speed. Its 5.3 litre Vortec V8 develops 300 horsepower and can switch off cylinders selectively, so that the engine works on fewer cylinders on the highway to extend range. It has four-wheel drive and measures 4.76 metres long and 2 metres wide. As a show prototype it was not sold to customers, but it displayed the hybrid and cylinder management ideas behind GM's fuel-saving full-size trucks and SUVs of the mid 2000s.