used in many '80s BMWs and certain Volvoes (mostly the diesels) will burn out their internal clutches if their motors are reved up while in neutral or park after being warmed up -- this requires a bunch of special procedures for some states' smog tests, and also leads to disasters for kids who like to keep working the throttle pedal while sitting at stoplights. Freewheeling with the engine off depends on how the particular transmission has its oil pumps designed and driven.