I'm having sort of a different problem with mine. No whining noise, but when it gets cold out, and even sometimes during the summer, I have no power assist while sitting still. Makes parking in a parking lot a pain. Even does it when the truck is at full operating temp. If I'm moving though, even less than 5mph, it works fine. And I have changed over to the Valvoline synthetic PS fluid. I read somewhere on here that theres a fitting in the back of the PS pump and if I take it out, theres a mesh screen in there that could be blocked up with debris and that there is a spring in there that I can stretch out a bit to gain a little extra power assist. Is this all true? If so, could this be my problem, and how much do you stretch the spring? Maybe its just time for a new pump.

 

when you stretch that spring you raise the relief pressure setting. effectively raising the operating pressure of the system. I would personally shim the spring to raise the relief pressure rather than stretch it.

with any hydraulic system, higher PSI will allow you to do more work.....higher GPM will allow you to that work faster.

 

could that screen being blocked up with junk be my problem though or is the pump just on its way out?

 

dad runs this crap in his 01 3500 and it only worked for a while

 

I just topped off with Synthetic and it seems the whine is gone, hopefully it stays this way. If it comes back I'll drain it all and put in fresh synthetic.