Chevy & GMC Vans

here is one for all you guys. ive got a 96 astro when i bought it it had a power steering whine, so i replaced the pump after 3 pumps 2 from autozone and 1 from oreilly's i decided to try a used one same whine with all of them steering is good i replaced the pressure line (pump to hydro) with one from advance auto . i have no leaks what so ever and at the present time am running royal purple synthetic fluid. i have tried almost all the different ps fluids nothing changes still the whine. my thinking is that either i got a bad hose and its restricting the flow or the hydro boost unit itself is the culprit anyhelp from you guys would be a big help.

My power steering has been making noise pretty much since I got the van. It's more of a moan or groan at low speed. At high speed, like on a curvy highway, it becomes a whine. I never figured out what it was, but the steering works fine, so I got used to it. I wish I could be of more help.

There is a TSB out there somewhere which speaks about the lines orientation. The pump also has a certain pressure requirement.

Look at/for those two items.

Jim

thanks i'll check them out...i should state that at idle its quiet anything above that you get the whine

Mike, how's that P/S pump doing? My does the same thing.

Ray

Hi,

I recently changed both ps pump and hydro boost on my 2003 AWD Astro which has 130,000 miles.
I too changed pressure hoses and I used ACDelco fluid. I flushed the system with 3 qts of fluid, as per shop manual, etc.
I also, used amity vac and bleed air from system.

It works well and is quiet.

There is a good You Tube video that shows how to replace hydro boost. See Eric the Car Guy on You Tube.

Also, I have replaced the OEM power steering cooler lines behind bumper with finned cooler located on lower left side of the radiator.

AP