Previously, the only full-size trucks equipped with EPAS were the General Motors two-mode hybrid pickups and SUVs. These machines powered the system from the 42 volts available as an off-shoot of the high-voltage battery. All F-150s powered by the 3.7-liter V6, 3.5-liter Ecoboost and 5.0-liter V8 will use the on-demand, electric motor-driven steering assist in place of the traditional, always-on hydraulic system. Only the specialty Raptor and Harley-Davidson models with the larger, heavier 6.2-liter V8 will retain the old system. EPAS is expected to contribute a fuel efficiency improvement of up to four percent thanks to the reduced parasitic losses.