Power steering pump question

I have a 1998 Dodge 3500 SLT Laramie Diesel supercab Dually. I bought the truck new and it really has been a good truck so far. I has only 90 thousand Kilometers. (Canada here)

In 2000 I took the truck to the Dodge dealership as I had a whine in the power steering pump that would be very loud when I started the truck on cold mornings (-10-20 Degrees Celcius). The power steering pump would whine when the truck sat idling until after about 2-3 minutes or so. It sounded like the pump was being "bottomed out " or the pump was low on oil. The Dodge dealership said that these trucks come from the south with heavier oil and we should be using a lighter oil up here in Canada to deal with colder temps....so they drained the steering pump and put in a lighter synthetic oil for the cooler temperatures. I thought the problem was fixed as the sound went away for about 5 years... Now I get a whine when I turn too sharply and can feel it in the steering wheel without "bottoming out". It's not even cold outside yet....It goes away when I am driving straight and making slow turns...but when I turn sharp it really does whine... Oil levels are good.

My question is this:....is this power steering pump on it's way out?... If it is I have time to replace it myself....any tests that a guy can do with this pump? winter is fast approaching us and I don't want to get caught out in the cold....Thanks for any constructive replies... Jim

The fact that you can feel something in the steering wheel tends to make one think the problem is in the steering box.

If the noise can be heard with the truck sitting still, you can open the hood and try to isolate the noise to either the pump or the steering box.

Start with the easy fixes first. If it isn't the belt, drain the power steering fluid and replace it. John