P/S Pump troubles

[Daytonatunnel]

I installed a new rack on my car, figured I'd do it right and replace the hoses and the pump (which was leaking from the front seal). Got my pump from NAPA, which normally sells great parts. BUT, not this time :( 1st pump worked perfectly, but after a few days started whining like I have a Pete Jackson gear drive under the hood. 2nd pump made terrible noises and NEVER worked a lick. 3rd pump worked fine, but after a few days is starting to whine all the time like the first pump. It really is noticeable, not just a faint whine. Old pump never made a noise. I followed the directions to the letter every time, even spun the pump in the correct direction by hand before installing belts to remove any air bubbles. Belts aren't to tight either. What are you guys using for replacement pumps ? Does this sound like a common problem ?

[dagenham]

What type of fluid are you using??

[Daytonatunnel]

Good question, the fluid NAPA sells.

[k98dave]

"Type F" is best

[Laredo]

Ford recommended procedure for refilling / bleeding PS (BEFORE you start the engine) was to raise the front wheels off the ground, disable ignition, while cranking engine - turn steering wheel back and forth, lock-to-lock several times. If you start the engine without doing this, air bubbles in pump cause the vanes in the pump to "chatter" against the pump chamber causing whining noise.