Strange PS Pump issue (I think!)

I towed out to Ouray, CO and back last week for a family vacation and noticed that my power steering pump (or so I think) was whining when turning left.. but only going up and down Monarch Mountain/Pass! All the way there (to Monarch Pass) I didn't hear anything, but noticed the whine while coming down and then once down, never heard it again - on the way back, I heard it on the way up (left turns only again) and down, but once down, no more! I tried to make the noise on the way to and from work today, but was not able to duplicate it - same in my garage, had engine on, in park, my daughter turning the wheels all the way to the left, no noise. I think the last time I heard noise was pulling Monarch Pass two or so years ago! Maybe my truck just does not like that Pass? ;-) I do not have any leaks, and the fluid is where it should be. Maybe it is not my PS pump? Any ideas or things to test appreciated. I have no steering issues, and other than the slight whine on the mountain, no issues whatsoever. I am stumped and I don't just want to throw parts at it.

Thanks,
George

 

Firstly, how old and in what sort of condition is the serpentine belt??

Now is a good a time as any to loosen tension on it and then check EACH and EVERY pulley and idler wheel that it wraps around for bearing play and/or tightness. NONE of the pulleys should have any side play and IIRC only the PS pump pulley can have some end play. Alos, they should not be too tight o turn by hand or feel rough when turning.
Also the tensioner spring can wear out and cause the belt to no longer track right and run up against the edges of one of the pulleys.

 

Thanks for the reply. The belt is only a couple of years old and looks fine. Funny but I was thinking it may be the sound of a belt slipping - and it only happens when the engine is really hot (relatively) - I was hitting 217 ECT going up the hill (temps came right back down on the downhill) - oh, and on a side note, now that I replaced my fan clutch, I can hear it roaring now!.

I am pretty sure my belt tensioner is orig to the truck (165K on it now) so I will replace it and check the belt routing at the same time. I see there is a Gates tensioner that Geno's sells, and I can also get the Cummins part, any preference for one or the other?

 

Even with a new tensioner and belt on my truck (06) it will still slip a little when the fan is fully engaged climbing a steep hill on a hot day with the AC on, that fan takes a lot of power to run at full engagement.

Not sure whey it would only do it when turning, maybe just coincidence? Could also be your power steering fluid overheating and cavitation the pump but that would not go away quickly so likely not the issue.

 

At higher altitude the barometric pressure would be lower and the fluid would be more prone to cavitation. Similar to water boiling at 212° but if you raise the pressure it raises boiling point

 

Think about how many miles you got out of the original ... if you can afford the difference, genuine Cummins would be the way to go.

 

Thanks. I found the following thread https://www.turbodieselregister.com/threads/belt-tensioner-which-is-better.259752/ that says the Cummins part is made by Dayco which my local Auto parts store carries.

 

That's good...always a good idea to shop local. ..How much do they want for it??

That said, Genos carries the Cummins OEM for $125. which isnt too bad.
Amazon has the Dayco for $75...

I wonder if their is a difference in quality between the Dayco that Amazon sells and the Cummins branded Dayco ??

 

I've had no problems with Gates tensioners. We use them on some of our White Fleet vehicles. The Cummins tensioner is made by Dayco.

Dang it. I got treed.....

 

Autozone is the local shop according to the Dayco website, and it is 128.62 with tax (free shipping).

 

For that price difference I would just order the OEM Cummins through Genos and support the company that supports TDR,

That said, if you need to save some money, and in fact the Dayco is the EXACT same as the Cummins OEM (IMO in this day oem QC standards DO make a difference!!!), you might get it faster, and certainly get it cheaper on Amazon--

 

I had heat related cavitation on mine to when I was slightly low on ATF, and it also wined only as long as I turned the steering wheel and stopped immediately at straight.
I'd recommend to change the PS fluid first before using the parts gun on a problem that is so unspecified. In the end it's just a waste of money throwing parts away that are actually perfectly fine.