PS pump risk assessment

What are the odds that a power steering pump that leaks and squeaks
when it's cold and loaded up (e.g. parking lot maneuvering right
after startup on a cold day) is going to fail catastrophically? I
was planning on not going out of town until I have a chance to
replace it (which I was going to procrastinate until the next oil
change), but now I may be tempted to make the 1100mi round trip to
visit a friend in Colorado next weekend since the forecast is
indicating that my original plan to fly out there may not be
feasible. Thoughts? Has anyone seen one of these pumps seize
completely while operating?

Joe Elliott
'88 S4

Hi Joe,
Leaking is not common, but it happens. Many times its a hose, link, or seal. The squeaking could be something you have not looked at. Here's what I had.

The car started to make squeaking sounds, typically when at low speed. Speed varied with engine rpm and went away shortly after warming up the engine. It came and went from time to time. I ignored it at first, but as it stayed on longer and went louder at some point I started to worry. It sounded like some bearing is giving up and getting stuck. Checked every bearing I could think of and all seemed ok. Thought about everything that could possibly go wrong and saw myself pulling the engine (hehe... remember Walt...?)

As my worry grew, I noticed that it became louder while turning the steering wheel when cold. It had a very good look at the steering pump, to see that the pulley was loose. The pulley moved over the hub when cold, and due to heat it seemed to luck up at some point. One bolt was broken and the others were loose. It took an hour or so to remove the broken bolt with grip pliers, clean and reassemble. Perfectly ever after.

Hope this helps resolve your (or someone else's) squeaking issue.

regards Theo

1992 928gts Midnight Blue (2006-)

1988 928s4 Cherry Red (1999-2006)

The Netherlands


I've rebuilt that unit and considering the design I don't think it will
seize. Haven't heard of it seizing, but if it runs dry it might.

Keep the fluid topped off. If the fluid starts to just run out then
remove (cut) the belt. If it does seize, then cut belt. The steering
will be heavy but will not leave you immobile.

The squeaking is almost certainly coming from the belt slipping because of the high load on the pump, not from bearing failure -- I don't think the bearing can be un-lubricated while the system has fluid, and I've seen people drive a long time, maybe weeks, with "no" fluid in the system (obviously, there was enough left to keep the power steering pump bearing lubed, but no power assisted steering and more leaking.

Ray (too much experience with poorly maintained cars)