Power Steering Squeal - puzzled

[Enoob]

I have an 01 Yukon and recently replaced the power steering pump after a failure. The new pump worked fine, but after about 2 hours of use, the pump seemed to give off a loud squeal. Seemed to come directly from the pump, so replaced it thinking bad pump. The new one again worked fine for about 2 hours use and the same squeal came back. Seems to increase/decrease with acceleration. Don't think it is the belt, but not sure what to really check next? Thoughts? Thank you.

 

[sparg93]

Not sure how an '01 differs from my OBS, but any chance the sound is coming from the AC? (mine is right about the PS pump)

Also, did you check your PS fluid level after you heard the noise? What type of fluid are you using and what brand of PS pump did you buy?

 

[Enoob]

Good call. Sounds like it is the AC afterall....I was going with my wife's comment that the noise was back.......different noise.....lovely. Thanks for the comment......

 

[Enoob]

Much to my dismay, the squeal is in the pump. Any suggestions as to things to try to eliminate the squeal, or, am I on to my third pump? Anything I could be doing wrong to cuase a squeal??? Thanks.