Now that the weather is turning colder my power sterring pump whines incredibly loud at startup.. I'm sure the whole block is looking out the window, and it ain't that cold yet. So I was going to change fluid and try Royal Purple syn fluid to see if that would help. In summer Lucas Bros fluid really helps quiet the "Ford Whine" but it makes it that much worse come winter. Right not I just have the Ford stuff in there but its still horrible. I recall someone telling me I'd need @ 4L ? Our fine owners manual does not list the capacity. Anyone know? I ordered 5 units fo RP stuff but they're only 12 oz units, so not enough....