The power steering pump in my truck was replaced not long after I got so it's still fairly new. However, it makes a loud noise when I start it up if it's colder outside. Is this normal? Or could there be something wrong? The noise goes away after the engine has warmed up a bit tho.

 

It probably has an air bubble trapped in it. Perhaps the guy that installed it didnt bleed it properly. Ive heard adding a ps filter helps cure this problem. Not sure how but maybe it slows the turbulance before the fluid enters the pump.

 

I had a '99 F-250 Powerstroke that did that as long as I owned it. Once the temp cooled down that thing whined like a two year old kid. It always worked fine. Even after driving for several hours it would still make racket. If it did not do it before but does it with your current pump then I would assume it is the pump. I thought about trying to find a lower viscosity (thiner) powersteering fluid like ATF to see if that helped. Good Luck

 

what fluid are you running? my truck used to do that, but when i changed the pump and everything else, i used atf type f and no more problems.

 

I'm using regular power steering fluid in it. The dip stick fell out of the old pump and a new pump doesn't come with a new dip stick so I've got one in there that kinda fits, I had to cut it down quite a bit. but could this be my problem? That colder air is getting inside the pump? I think I'll add a little fluid to it tonight if I have any and seal the filler temporarily with tape to see if that could make any difference in the morning when I go to work.

 

can you take a pic of the pump. i probibly have a cap that will fit it but i would have to know what cap to look for. there are 3 diffrent styles if im not mistaken.

price, just cover shipping and id be happy.

 

Well I know it's not one of the big round ones. I'll try finding a pic of the ps pump I have online and posting it. It's easier than going out and snappin a pic and posting it lol.

 

This is the cap I have. Found it on napa's website for $7

 

ill check the shed tommarow to see if i have one, i think i gave lee my last one a couple weeks ago that was that style. and $7 is probibly what it would cost to ship it from IL to AZ lol....id say just go to napa to be honest

 

probably what I'll end up doin either tomorrow or saturday. It'll be the easiest part of my weekend project lol

 

Pump whinning is a result of cavitation. Large amounts of air will work its way out during normal use.
Often times we fail to realize that some fluids are not compatable and can foam during use. This foam contains air, and this air is what causes the whine.
Power steering fluids and transmission fluids are different, and can foam. If this vehicle had ATF before and regular power steering fluid was added, it can cause this problem.
The same is true for the opposite.
By design this pump is known for this whine, and thie again is by the design of the gears in the pump, but it can be controlled. This means that the fluid has to be clean, and not contaminated.
In this case the saginaw pump upgrade is a real plus, and adding fluid capacity helps out with any pump.
An additional cooler serves two purposes, and this is the obvious, keeping the fluid cool, but also adds fluid capacity. Fatigued fluid should be changed and fresh fluid will help.
Most forget, or overlook power steering fluid changes or maintenance. Often times they get left alone and never see any type of maintenance.
Changing the fluid is a real must.

 

How would I go about changing the power steering fluid? And does it make a difference between using atf or p/s fluid? If so what what would you guys recommend?

 

I use ATF, and I use only ATF.. I use it because I only have to carry one type of fluid in my first aid kit. makes it easier when I have to repair on the trail. (not if, when)

Often times as I mentioned above, fluids that are not compatable can foam, and foam is aeration, and this is bad. Air permits small portions of metal to metal contact, and this is a form of cavitation. This is often times where the whinning comes from.
Overheating fluid can cause this too. As the fluid breaks down it becomes less effective at doing its job, and eventually fails, or a component fails.
Anyway, to change the fluid, one can remove the return line, and crank the engine (without starting it) and drain out the old fluid while adding fluid until fresh clean fluid comes out. Then install the return line, and check for proper levels.
Or one can use a turkey baster to remove the fluid from the reservior, and then run the pump and continue removing fluid until you are satisifed that the fluid is free of old contaminated fluids. Suspended particles will discolor fluid, and make it less effective.
Good fresh fluid helps everything.

 

Make sure you don't have any hose leaks. Leaks are an indication of a place that air can be drawn into system.
You want to pressure wash clean the area around your pump and hoses to check for signs of fluid.
Check hose condition and connections and any o-rings. Replace if in doubt.
Shine a flash light into the reservoir while running. If the fluid is very milky or foaming, air is being drawn into system.
If the pump has been drawing air for very long it will become damaged.
The pump will become damaged from the air being compressed as it goes through the pump. As the air bubbles compress the temperature of the compressed bubbles skyrockets and scores the metal walls and vanes of the pump causing whining.
Power steering pumps are vane pumps (not gears) and easily damaged when installed. They should be bench primed before installation to eliminate as much air as possible and prevent a dry start. Dry starts will make them whine forever.

Heavy knocking is an indication of "Cavitation". Cavitation is caused when the pump can not draw fluid due to a blockage (filter or strainer stopped up) or oil too thick(when cold) or combination of the two. This creates a high vacuum that turns the oil into a gas state and damages to pump much like air but more violent and louder.

Whining is excessive pump wear and damage or is an indication of "Pseudo-Cavitation" which is outside air being drawn into system.