My 1992 f150 4.9L inline six makes a loud wining noise when I take turns, I was wondering if this might be the power steering pump itself starting to go, but it still handles fine. any ideas?
My other truck, a 1987 F150 5.0 EFI has a similar problem. It wines and studders then bogs down until I straighten out the wheel. What could cause this?

 

Check the fluid in your pump on both. Probably a little low. Mine does the same thing.

 

Ford's notorious for loud PS pumps. I can't say I've ever heard a quiet one in the 87-96 vintage of trucks. But, check your fluid, then bleed the pump, that will definitely help. If it gets too loud, change the pump.

Jason

 

I agree, check your fluid but chances are it's the normal Ford PS pump whine.

 

There is no significany procedure for bleeding the pump...it's different than brakes or hydraulic clutches. Therefore, don't worry about bleeding it.

Ford's truck pumps are fairly loud but...most of the time you can't hear it. The only time you should be able to hear it is when your parallel parking or some kind slow turning manouvers.

My buddy's 96 F-150's pump is bad and I can hear it from just sitting in the cab at idle. The pump works ok it just whines. If the fluid level is ok, and the pump still whines...the only thing that can be done is to replace it. Dirt is probably the cause, these units don't like dirt one bit.

 

Fluids levels are OK. Im not too worried about the noise, but do you think a bad pump would make your truck bog down when taking turns? Thats what i really want to solve.

 

Jesus Christ...JustinD_F150...guess what my last name starts with....didn't notice that the first time around.

It's a good possibility the bogging while turning is from the PS pump.

 

I was just talking about stop-to-stop bleeding. It's a recirculating pump, so it would pretty much bleed itself eventually, but it never hurts to do it after you top off the fluid, or if you have to replace the pump. All you have to do is, with the truck running, turn the steering wheel all the way to one stop, then all the way to the other, and repeat this a couple times.

Jason

 

The power steering pump in all fords bigger than a Tempo/Escort whine, part of it is the design of the pump, part of it is the system likes to trap air and dirt

To bleed and replace the fluid:

Disconnect one hose off the power steering pump, preferably the one closest to the ground while you've placed a bucket underneath the frame rail.

Take off the power steering resevoir cap, and let the system drain.

Replace cap and hose, and refill the resevior half way.

Idle the engine to bring the hydraulic steering fluid to operating temperature (60-80 C degrees, 140-170 F degrees). Do not turn the wheel until the truck warms up (5-6 minutes)

Add fluid to bring system up to proper specifications.

With engine still idling, cycle the steering wheel from side to side 10-15 times. Do not turn too quickly or hold in the lock position for more than 10 seconds.

Refill the power steering pump to proper specifications.

Check hydraulic fluid for color—if tan, light red, foamy or cloudy, air is still in the system. Repeat the idling, turn to lock to lock, and add fluid steps until its full and the right color. Sometimes letting the truck sit, powered off for 30-40 minutes can help if you're really struggling with air bubbles.

If all the air is not removed from the system, an abnormal intermittent whine, moan or continuous growing noise may be heard form the power steering system. In some cases, a "shudder" may be felt in the steering wheel while driving the vehicle. If possibility of an air leak exists, check the entire system for leaks, repair as necessary and bleed the system.

 

Oh man.. Loud power steerings on those Ford are as common as thoes junk Mazda trannys going bad. This post is actually funny to me just because I know a few people with the worst luck with those pumps. My brother had one that performed great, just made so much noise. I have a buddie that had one and it drove him completely nuts, so nuts that he had replaced it..?..lost count at about 8 times!! He could never get a quiet pump. I have an 88F-150 and somehow, mine is whisper quiet. I dont know how but if I ever sell that truck im pulling it out and just keeping for the sake of keeping it.

 

I'm not an automotive expert by any means but I had a similar whine when turning a while back that came out of the blue. I would watch the voltage drop when I turned down into the 8 or 9 volt range. I replaced the altenator and found out the belt tensioner pulley was completely seized. When I fixed those two problems, the whine stopped and so did the bog when I turned. Just an idea. 93candycane.

 

93candycane is correct, it may not be the pump. I think we all jumped on the pump idea because its extremely common (like, 8 out of 10 vehicles), and he mentioned turning the wheels initially. But that doesn't preclude it being something else for sure.

5.4A - flushing it does cut down the noise significantly *if* its flushed when it first starts making noise... once its whined for a while, its not going to stop.

Mine is as loud as my exhaust... I have a GM power steering pump sitting right here... and I'm seriously considering adding yet another non-ford part to my truck

 

I've read they whine because of bigger clearances from wear. The clearances cause small internal leaks as the pump is operating (not enough to affect operation) and that's what makes the noise. I'm sure reman pumps whine because of bad reman/manufacturing tolerances. Just a fact of life.

I did have a fairly loud pump on my '91. The oil looked like mud. I changed the oil several times until it was nice and clean and red and it did quiet significantly.

I put a drain pan under, pulled the hose off the back of the reservoir, put another plugged hose on the reservoir to keep fluid from running out, and turned the pump by hand until the reservoir was empty (belt off of course). Then I filled it with clean fluid and turned the pump by hand. I kept topping it off and turning it until the return hose ran clean fluid. Then I put the system back together, started the truck and cycled it back and forth lock to lock a couple of times. The fluid was dirty again from the fluid out of the steering box. I repeated the whole process about 3 times until it stayed clean. I probably ran about 3 or 4 quarts through. Much quieter, but you can still hear it just a little.