Colorado power steering groan

I have a 2004 Chevy Colorado 5 cyl. w/ 48,000 miles. After the engine warms up and when I turn the steering wheel even a little, I hear a groan or moan that sounds like it’s coming from the steering column where it penetrates the firewall. I’ve had to use lithium grease on the brake linkage firewall penetration to eliminate a “rubbing” sound, and so I thought I might have the same fix with the steering column. But the fittings are so tight, I can’t find anywhere to lubricate. The power steering fluid is full and clear; the belts are fine. The dealer says they’ve never replaces a ps pump and thinks maybe a $105 flushing of the ps system might fix the problem. I know a groan can signal a ps pump going bad, but there is no grinding sound and the steering works fine. Any ideas?

GM has a TSB out about noises that can eminate from the intermediate steering shaft on some vehicles. Gm is in litigation with the supplier of these shafts claiming it was supplied with inferior components.

Here’s what some people do to eliminate noises from these inferior intermediate shafts. http://www.youtube.com/watch?v=6GigDxHKz2Y

Tester

If the noise is coming from the PUMP, check to see if the filter screen in the bottom of the P.S. Fluid reservoir is not plugged up with hose particles, starving the pump…

Thanks. I might give this a try.

Thanks. I’ll check the screen.