A power operating system for opening and closing a vehicle liftgate has a pair of drive units supported on the vehicle pillars at the sides of the liftgate opening. Each drive unit includes a vertically oriented channel and a rack bar that moves in the channel. A link is universally attached to the rack bar at one end and universally attached to the liftgate at the opposite end. The rack bar is raised and lowered by a power unit that has a motor driven pinion gear that meshes with the rack bar. Raising and lowering the rack bar opens and closes the liftgate via the link.