Bill, you are experiencing what thousands of other Ford owners have experienced. The original pump most likely started making noise and now after replacing it several times with an aftermarket pump, you still have a noise.
Let me start by saying, everything you have done and ImpellaSS has recommend it accurate and should have taken care of the problem. However, all I can tell you is this (and this comes from years of experience) for some reason, the aftermarket pumps make noise like you are low on fluid even though you are not. I can't tell you if the manufacturers have different tollerances that they follow that allow fluid to bypass the pump or what. The only fix that I have done successfully is with a new factory pump. That was the only way I ever got rid of the noise.
Now keep in mind, even though the pump is making noise, doesn't mean it is bad or will leave you stranded. THey work but are annoying!
Also, I read through the your postings. Everything you did is correct to bleed a pump. The fact that there is no foaming in the resivour tells me you did the job correct.
I wish I had a better answer for you, but I am offering my past experience to you. In fact, I have a brother-in-law that I replaced the pump on his windstar for him. I told him to get a factory pump, but he insisted I get the cheap one at the local parts store and it does the same thing. Now it's a running joke in the family that I sell junk parts.
Let me know if you have other specific questions. Again, I wish I had a better answer for you, but with 30 years of experience working on cars, and dealing with this type of problem for the past 10+ years (on fords only) that is the best I can tell you.
Joe
Sunday, October 11th, 2009 AT 9:17 PM