General Motors has pulled the optional four-wheel steering system from the 2006 truck option list. Poor sales brought the end of the expensive system. Quadrasteer would turn the rear wheels in the same direction at high speeds for better stability and the opposite direction at low speeds to aid in maneuverability. Demand for Quadrasteer never exceeded 2.1 percent over the four-vehicle line – GMC Sierra and Yukon XL and Chevrolet Silverado and Suburban – it was offered. The option was priced at $2000.