me too, I think its a wheel bearing. Originally thought it was hub locking up because when I shifted into 4x4 it would correct it for a while. Bought new manual hubs when I went to replace passenger side it would not slide in. Spindle was off center and can be moved when tapped. I think it was locking up drive shaft when it moved. I will be pulling it off tomorrow to verify. Funny because I didn't notice it when I checked 2days ago. That hub would not turn so I assumed it was the problem. Today that hub was busted up when I pulled it off,

 

That's what my hub was like. I had a seized u-joint. Haven't had steering issues since i replaced it.

 

To add a conclusion to my steering gremlins , I took apart the right side suspension where the wheering noise seemed to be comming from. Found bad right side wheel bearing and a seized right axle u-joint, 100 miles later and seems to be running fine ...so far . In the process also replace right knuckle seal which seems to resovle problem with the left hub releasing (seal probably fixed vacuum leak on right side).

 

I am in no way an expert on Fords, I am an experienced HD retired mechanic that is learning the little stuff. A friend had a 99 Ford 3500 Diesel that would jerk the steering back and forth, the "U" joint, one cup was welded solid, the Warren hub was destroyed from the fact the "U" wanted to straighten the wheel out every 1/2 revolution. It did this weather the hub 4 wheel drive was engaged or not.
When we got the axle out I had to cut the seized end off as it would not come apart.

 

2000 ford f-350 4x4 crew long box-jerking back and forth found a bad Hub Bearing changed it. Changed calipers and pads still happening and now its tearing up my rotors cause when it binds up i guess it throws everything else out. Will check u-joints in the a.m. Replaced power steering pump about a year ago but I do notice a whinening sound , I am running 40" Irok radials. I have seen the brake lines collapse on the inside of the rubber hose from frame to the wheel on other Ford vehicles so when the brakes are applied and let off they stay stuck, which is what I thought might be happening but after reading this thread from begining to end I'm not sure. I will follow up with my findings

 

We replaced both Warn hubs, and all is perfect now.

 

Were the U-loints good?

 

just an update date on my past problem, 10,000 mi down the road and all is good after replacing front right axle U-joint(seized) and right front wheel bearing(very noisey). Warn hub was in good shape and clean, just added a little more fresh grease. As a matter of PM I replaced ALL seals. Its worthy to note that the front diff tube dust seals have been redesigned because the original wear out quickly (both of mine were totally gone). I guess this means that this summer I'm tearing into the left side. Also highly recommend Spicer U-joints over joints like Precision (just don't seem to have the same level of quality as a Spicer but the Precision are CHEAP).

 

The "U" joint was the original problem, it had one cup welded solid, I had to cut it out..
When you rotated the wheel with the steering off center it would jerk straight.

 

my 03 ex is doing the exact same thing.It like darts ,or timed jerk .no mechanic either but I am 99 % sure I know what mine is.I made the mistake of buying ball joints on line, I thought ball joints were ball joints . they turned out to be made in China and the mechanic said nothing to me untill they were installed .So iam sure I will have to have them redone.But my truck acts the exact same way that you are saying yours does. Darts and jerks all over at different times and speeds. And Iam sure its ball joints.They might not only be to tight but out of round or something.So take this for what its worth.

 

My customer is a retired mechanic as well, we tried looking up everything we could fine both of us are Heavy Duty Mechanics, We pulled the hub out thinking that was the problem but there was nothing wrong with it, we put it together and tried it again.
The next day we were worried it was going to destroy the steering box, and we figured it must be the axle shafts were bent, so I pulled it completely apart and found the "U" joint sized solid. I put the stub end and the longer shaft in my lathe, and they were all straight.
We bought the parts in Orville Washington, and a plastic pipe bushing I turned in the lathe to make a seal driver.

 

That doesn't sound like ball joints.

 

Never heard of a bent front axle on these trucks.

 

Neither had I but, I have never seen a "U" joint cap seized solid, I worked class eights, the little stuff is a learning experience for me I always did, a lot of small stuff not a lot of Ford 1 tons.
The reason we were looking for a bent axle was that would give you a jerking motion, the shafts were perfect.

 

I have a 2001 Excursion That has been getting steering problems for the last few months. I have had the front end looked at twice and the only found problem is stiff ball joints on both sides. The steering issue is that while driving straight down the road you can feel it start to pull to the right and then either give way jerking back to the right or I will physically over correct it myself to bring it back to center. It has gotten to the point that it feels like its on a timer of going every minute or so then release. Once after turning left I had to hold the wheel turned 1/8 of a turn to the right to keep it straight until I got to a spot on the road and gave it a jerk which corrected the issue.

Now my wife is telling me that it still pulls to the right and now when she turns it back to the left she is hearing a clicking noise coming from the steering. I have talked to another mechanic and he told me about the seal in the gearbox going bad but ther eis no good way to check it while on the truck. After 15 pages I see the problem is most likely the steering box, but did anyone actually replace the box and fix the issue?