I have been very happy with my truck, with no complaints since I bought it new... until this winter that is.

Now when the temperature is below about 30 and the truck sits outside for a few hours, starting the engine produces a very loud "wine" or "screech" for a few seconds that dissipates gradually. Also, steering is very hard for the first 20 to 30 seconds. Neither of these symptoms have ever happened before this winter.

For the screech, I thought it sounded like it was coming from the serpentine belt, so I replaced it, which had no effect.

For the hard steering, I tried replacing some of the power steering fluid with Lucas power steering fluid (someone recommended I try this) which had no effect.

I'm now wondering if the two issues are related. Could it be the power steering pump that's causes both issues? Any advice would be appreciated.
Thanks.

 

that would be my guess. there is a power steering hose that goes to the rack that leaks when it gets cold out and I would bet that all the steering fluid leaked out and burned up the pump or at least started to burn it up. search the DIY for the fix for the leaking hose then replace power steering pump.

 

Actually, the power steering fluid level was normal and I removed some to replace it with the Lucas fluid. However last summer, I did have a leak that was subsequently fixed, could that have been enough to fry the pump?

 

are our PS pumps belt driven?

 

(I can't type...see post below lol)

 

I've had my truck for 2 winters now and each year there was a leak from the PS hose..check your hoses and your pump and see if you are leaking there..I know what you're talking about with the whine and the hard turning when you first start driving..thats exactly the way it was with me and it was due to my PS hose leaking

 

From the description. I'd lean towards a bad power steering pump. If the leak you fixed last summer was bad enough and fluid level got to low. The pump could have pulled in some air and cavitated. Which could have worn the impeller a slightly. Also it might not have been noticeable tell the winter because the summer weather was hot enough to keep fluid flowing easliy. Steering fluid flows better warm than cold. That could also explain the screech from the pump when cold too.

 

Damn hit all the wrong buttons. The pump works harder until the fluid is warm and then you don't notice an issue anymore. It also explains why it happens every time the truck sits for a few hours. OK that was my two cents in two parts. Hope it helps.

 

Yes, our power steering pumps are still belt driven.

 

OK, a little more information: There are no leaks that I can find, so not a leaky hose. A mechanic recommended that I have the power steering system flushed, but since I had already had that done about 5,000 miles ago I'm not sure what good it would do to do it again so soon.

I thought originally that it sounded like the belt was slipping, but now I don't think so as it seems considerably lower in pitch. I tried to visually verify if the PS pump pulley was hesitating or that the belt was slipping on it and couldn't. However the sound definitely emanates from the general area of the engine where the PS pump is located.

The hard steering is present even after the whine is completely gone. In other words, I started the engine, let it run until the whine stopped and then started to drive and for the first few moments the steering was still very hard.

Before I go through the effort and expense of replacing the PS pump, are there any other possible causes? I'm going to try and get a recording of the whine over the weekend if that will help.
Thanks for all the comments.