milehighXR wrote:Lower weight by not having pump, hoses, or hydraulic rack. More MPG(and HP) by not having parasitic loss from driving the pump, of course these are logical assumptions...
If you look at the motor that's attached to the rack, you might not believe there's any weight to save over a hydraulic setup. Plus, what you gain by eliminating the parasitic pump you may lose in driving the alternator harder. The electric PS motor draws a decent amount of current.
I suspect Ford went to EPAS because it's easier to package than the hydraulic system, the installer need only connect an electrical connector rather than attaching high-pressure hoses and adding hydraulic fluid, and most importantly,
they can now vary the steering effort anytime. Now they can provide more assist at low speeds to help you get though the parking lot, and then decrease the assist at speed. There's no more compromise, and it makes for a great drive.