Hi, I have a 1995 Chev Tahoe 4X4, 5.7L. 134k miles. My problem is the air Conditioning. It blows cold, no problem. It just sounds like a jet engine. This is the second pump we have put in. We put in the required oil and the proper amount of refrigerant. I might ad that we have done other AC units before on other makes with no problems. The first pump (original) slowly got louder as time went on. So we replaced it with a reconditioned one. It still makes the same noise. As I said, It blows cold, but being in Arizona and given it has a sereintine belt, I don't want it to break down in the middle of the summer. We have now perchased a third pump and a new accumulator and oriface filter. Before we put these on, can you possibly tell us what we might be doing wrong? Or do you think replacing all three items will cure the noise? Thanks.