2003 Trailblazer, had a power steering fluid leak, repair guys wanted to clean everything up, and run for a bit to figure where the leak was coming from, so I ran low a couple of times in 2 weeks on fluid, ps motor was not happy, probably 20k ago, leaking line at rack and pinion, every now and then, like maybe a month apart I get a power steering motor whine until warmed up.
Any miracle in a bottle suggestions?
The whine you’re hearing is the PS pump.
So, what’d they find? Did they find the leak source?
A hose, or tube was rusted out, both lines were replaced.
There are 2 lines, pressure line from pump to rack and return line (much lower pressure, sometimes uses rubber hose for part of it) back to pump.
The pressure line is usually shorter and less expensive. The return line can be very long because of a “cooler” section that is located behind radiator, so it runs from behind engine to the front of vehicle, across the front, and back down the other side to the pump.
Access (for line replacement, depending on which line) is very difficult on some cars and is labor intensive.
Do you know which line is leaking and did you get an estimate?
I have found good quality aftermarket return lines, but it’s the labor that is usually quite expensive.
A return line (the low pressure one) can sometimes be repaired with rubber hose design for PS use.
I had a leak in a return line near the radiator in the “cooler” section of the line (caused by a stupid metal clip on a wiring harness that rubbed a tiny hole in it). Repair cost estimate was very expensive, so I used a mini-tubing cutter, cut out a 1/2" length of the tubing and repaired it using a 3/16" brass compression union ($3) from the hardware store. Total repair = 3 bucks!
Low fluid OR air entering the line (like through a leak) can both cause a whine. Trust me, I know.
I was getting that until I repaired the leaky line. The noise stopped as soon as the leak did. As long as the pump isn’t damaged that should be the result.
I gave our old Impala to my son to use about 5 years ago. It had a leaky PS pump that would sling fluid up where you could see it on the hood. Before I could do anything with it, my son bought and added some “miracle in a bottle” PS leak stop.
I would have never done it, but I didn’t say much (bit my tongue) because the damage was done I thought.
I’ll be danged, but that stuff stopped the leak and it’s been four years and another 100,000 miles!
Since then the car was used by my daughter for a couple years and then we got it back.
The PS is still going strong with the “miracle in a can” and the compression union splice is just fine. Car has over 300,000 miles and is 17 years old.
Hope that helps. Keep talking.
CSA
EDIT P.S. I believe there is also another short line on the rack that runs from one part of the rack to another part. I’m going to have to look a diagram.
Both lines have been replaced, no leaks, level is fine, it was done a couple of years ago, Just the once a month or so whine of the motor on startup leftover from previous abuse I assume is the only issue.
It is not a loud whine, pretty minimal, but still a concern.
That information would have been helpful in your original post… ha, ha! 
You’re sure it’s the PS?
Does the noise change when you move the steering wheel back and forth, car parked, engine running and whine present?
CSA
Sorry CSA I am not positive it is the power steering motor, but from the subtle sound 99% sure. For the couple of minutes on the infrequent times I hear it backing out of the drive into a 90 degree turn at the street, I do not notice any change.
It is more prone to happen in cold weather I suppose. My thought is it is not at the level of time for a replacement pump, but just wondering if there was an additive that may prolong the life.
Just go to an auto parts store and look in the “Magic Elixir” section and choose.
Would it whine in your driveway just after start-up? If so, open the hood and have someone turn the steering wheel lock to lock while you listen under the hood for the location of the sound. If you have an automotive stethoscope or a several foot long piece of Tygon tubing you could also use that to help locate the spot. Use the tubing as a stethoscope, if that wasn’t clear.
Another possibility - alternator bearings.
I had good luck with a power steering stop leak product. Not sure which one but think it was Prestone. I would lose fluid and think I had even replaced the pump a while before that. At any rate, one dose and never had a problem after that.
No leak now.
From my experience, a stethoscope will locate certain sounds better than tubing, and vice versa. I would try both. Stethoscopes are 5 or 10 bucks. Tubing is less.
Just be very careful probing around moving parts! Sometimes you need the stethoscope to probe vibrations through a stationary nut in the center of a spinning idler pulley hub!
CSA
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Great ideas as always, but it is so intermittent at this point, and will try the stethoscope to try and pinpoint any irregularities, but in all practicality it will probably be drive it until it presents itself as a problem. My hope was there was a special additive to improve the power steering motor life, but there does not appear to be one.
Happy Memorial day.
For the record, a hydraulic power steering system has no “motor”. The way it works is that a pump driven by the crankshaft via a “fanbelt” pumps fluid through the system constantly, and when you turn the wheel a special valve directs the fluid under pressure to one side of a piston in the “rack” or the other side, depending on which way you’re steering. Here’s a diagram of a typical power steering system.
Modern electrical power steering is different, but you have a hydraulic system.
There are countless “miracle” products that promise to fix a bad power steering system. And probably a few “faith healers” that will make the same promise. The “miracle” additives are about as good as the faith healer. don’t waste your money. A pump making noise under load is a pump on its way out.
Did you have the entire length of lines replaced or only leaking section? Reason i ask is this design has 2 weak points and way more line than necessary. First weak point is down by rack you mentioned. Second is on left strut tower. Some fool designed the mounts with a 4" section of rubber that completely encapsulates the lines and traps moisture. I pull those out and just tywrap the lines to a nearby hose. Even my 08 was close to rotting out from these while the rest of the hardlines look like new…
Yes both lines were entirely replaced, Bad decision to use the rubber it sounds like,
Again, beware the red herring! I’ve been lured in by that fish before.
The Power Steering problem(s) leads one to logically assume that is the cause of the occasional the whining sound. It makes sense. It could actually be that.
However, it could be something else. I do see lots of hits for an idler/tensioner pulley bearing whine that has tricked some folks when I search Trail Blazer power steering noise.
CSA
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Yes it could sure be something else, my plan is to fix it when it breaks. Tensioner was replaced 4 or 5 years ago, but we all know that does not mean anything. My tensioner noise was like valve chatter on startup that would go away after a minute or so, I did have dampness on the brake line rubber holder on the top of the fender well, it was an $800 repair to replace the brake lines, but i am happy with the car overall, and boat towing vehicles are not easy to find.
This discussion could be helpful for someone looking at this vehicle purchase,
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