Steering wheel yanks side to side while turning or hitting bumps

[Silver X]

My Explorer has been sitting for a few months due to a blown trans. I fixed the trans, but the truck developed a new problem while sitting.

The steering wheel has a shudder like there is air in the lines or something. It stays calm when driving straight, but tries to rip out of my hands when starting to turn more than a few degrees. It also does this when only one tire hits a bump. It saws side to side for a few seconds then calms down. Would a faulty PS pump cause this?

There are no leaks anywhere, and the fluid level is correct. None of the lines or any part of the system were removed during the trans repair.

All the details I can think of:
Before the truck sat, there used to be a squeal (chirp chirp chirp) when the engine was running, but the squeal is gone now...at least for the few miles I drove it yesterday. Last year, I replaced the belt, idler, and tensioner, but didn't make any difference. I couldn't identify where the noise was coming from, so took it to the dealership. They only replaced the pulleys again and sprayed crap on the belt, but it didn't help. I originally thought the noise was coming from the alternator, but now I'm thinking it was the PS pump. Is there any way to check it to make sure the pump's pressure is correct, etc? I don't want to buy a new pump, then not be able to return it if it isn't the problem. I want to diagnose this before throwing money at it.

Another thing...We had to move the truck in and out of the garage a few times when the trans was out. The steering wheel had to be cranked full lock in each direction to get it into the parking spot next to the garage. The steering wheel was very hard to move due to the tires being sunk into the soft gravel parking area. Could I have damaged something in the steering rack?

Anyway, the X will remain parked until I fix this latest problem.

 

[Silver X]

BTW, I tried turning it lock to lock several times with the engine running, but it didn't help. The fluid color also looks OK. It doesn't make any noises either.

 

[Silver X]

Just remembered...last year, before the trans died, the steering would slightly hang up turning from center during low speed ( <3mph ) coasting/idling into and out of parking spots. I thought it was just due to the low idle not giving the steering enough assist to move the larger tires.

Haven't really driven it since November, so I forgot about a few things it used to do.

 

[Redneck0907]

bump!

my truck does this, i think its related to have to turn the wheel with the engine off. my truck wouldnt start due to a fuel issue and i got it back and now it does this.. i had to turn the wheels for the ramp truck driver.. any tips.. im leaning torward intermediate steering shaft..

 

[Silver X]

Mine is OK now. It was probably just air in the system. I turned the wheels back and forth about 20 times, but that didn't help. After asking around, the same answer was to keep going lock to lock. Tryed it another 50 times and the problem went away.

The hanging up has gone away too.

 

[my98nnj]

Ford are notorious for this. Anytime you turn the steering while the engine is off it needs to be bleed. Lock to lock turns, at very slow speed in an empty lot usually does the trick. If the fluid has airated(sp?), it will take longer as the bubbles will have to settle up and out.

 

[Four0Sport]

my 93 had some steering issues a couple weeks back during a snow and some cold temps. fluid was old, brown, dirty looking.. took some out and put some new in and it seems to be working fine. hope so bc im driving that thing to work and back this week while the 97 is getting looked at.

last night my brother called me and told me he was out doing donuts in his dakota and when he was done the steering was hard to turn.. his fluid its brown.. a few bubbles, i think he got air in his lines. i went out and turnes his wheel lock to lock a few times and it helped. next is to suck out the old fluid with a suction gun, add new, work it, suck out old, add new, work it, etc..

luckily my 93 and his 97 dakota are both pump and gear box only, no rack.

 

[Redneck0907]

Once again thanks guys, just air in the lines... i didnt expect that but it does make sense now that i think about it..