Ford Super Duty Steering Wobble

...Timothy...If that were to happen in a curve you would find yourself in the bushes wondering WTF just happened....I'd get a video of that from a chase vehicle if possible...doing that might be of benefit...maybe lash a Go Pro down there and see if the steering box jumps around...that was outrageously violent and I'd have to change my skivvies afterward...Dan H. ...South Texas...

Ford TSB 19-2274 Issue: Sustained Steering Wheel Oscillation – Above 45 MPH (72 Km/h) Models: … F-Super Duty In all likelihood, this is going to be the same design flaw we've seen before--spindly steering linkages/track bar and too little caster--and it may never have a long-term fix from the OEM. Ford deserves a shellacking over this nonsense again. I remember the Dodges getting some…

Check steer tires for broken belts. Rotate tires from one of the rear Duals.

There is a TSB for an updated steering dampener. Also check track bar and ball joint for Play

check the caster had the same problem with Ram 5500 caster was out by 2 deg,

Those vehicles are prone to the death wobble. My experience is that its a geometry issue, caster seems to affect it the most. Maybe the frame stretch could be making the problem worse. Make sure alignment is good and an updated or updated steering stabilizer might be all that you can do.

With the front wheels on the ground, have someone shake the steering back and forth. Any movement on either end of the track bar is a problem. RS lower tie rod end is another common failure. Once all is tight an alignment is in order, you'll want to have the caster at the high end of the spec.

Although an updated steering dampener will help, the geometry of the suspension is the real cause. It's similar to a shopping cart wheel shimmy when hitting a bump or going too fast. There is not enough caster in the suspension of the truck or a weight distribution problem.

double up the steering damper, replace the track bar, dial in as much caster as you can. Anything else with any wear will need to be addressed as well.

Being as this is an F550 I assume its not a pickup bed on the back. Suspension ride height changes from the conversion/upfit will change the caster. For years this has been an issue typically on the F250/350 with a gas motor due to lower tire pressures in the front compared to the diesel of the same body. As said by others check the alignment and adjust the Caster to the maximum achievable…

I have had really good success on the Rams by using an aftermarket dual steering stabilizer assembly. Dont know if they make one for that vehicle.

Hey Timothy. Check for play in the track bar. Go under on a creeper and have an assistant in the vehicle rock the steering wheel back and forth. Feel both ends of the track bar for any play at all. I bet you'll find either some play in one end or the bolt on the left side has worked loose.

Even my 1977 Ford 4wd will get the death wobble every time the track bar bushings get 1/8" give to them. An everlasting maintenance issue with all coil sprung front drive axles. Leaf sprung front drive axles require the bushings in the "eyes"/ends of the leaf springs replaced for same problem on models that use those suspensions. The Ford steering dampeners are superior to man aftermarket…

Meant to say knuckle ball joints.

Acts like the jeep "death wobble" that fix is almost always steering damper...

I worked for Chrysler for many years. We had the same problem with Jeeps. The Wrangler was the worst. Check the alignment. I would make sure to check the steering dampener if it has one. We noticed that if the toe was out, usually a toe-in reading, and you hit a bump at a higher rate of speed it would cause the front end shake so bad that you would have to slow down to make the shake stop. I…

I was looking for an old TSB regarding these issues and found 07-10-10. This was for a different body style, but it stated to reduce the caster not increase as I previously wrote.

So both these TSBs are saying go negative with the caster? Can someone comment on why that is?

That is some confusing wording in the TSB, you're right. Increasing positive caster is what helps with this problem. Looks like somebody has already cranked the caster on this truck. One of the alignment guys can weigh in, but I'd say those numbers are pretty well as good as you can get. I say replace the loose/faulty parts and let's see how she does!

The front suspension on this truck is completely stock and still has the preset factory upper ball joint adjusters installed. Someone on the "other" network said that he was told directly by Ford technicians to go negative with caster. Think of a shopping cart caster wheel. That has extreme positive caster and thats why it trails. Negative caster would not work. Am I thinking correctly?

A shopping cart wheel axle is behind the pivot point(all negative caster?). The 'axle' of the truck wheel is in front of the pivot (positive caster). It doesn't state to go negative caster, but just less positive caster. I would trust the adjustment should help as long as there is no play in the suspension/steering.

A shopping cart front wheel has positive caster, a lot of positive caster, that is what keeps the wheel pointing in the direction of travel. Positive caster is what helps return the front wheel to the straight ahead position after making a turn. Think about how the steering feels when backing up, if you back up fast and turn the steering wheel it tries to turn the wheel through the rest of the…

Positive caster increases the tendency of the wheels to straighten out on their own. Thinking of it more like a wheel barrow, the closer to parallel with the ground, the more stable the wheel barrow is, the less it wants to turn (lots of positive caster). Lift the handles higher, stability goes down, but turning becomes easier (less positive caster). Now that I'm thinking about it though, maybe…

No, that is not correct. Have you ever pushed a shopping cart really fast or seen it done in person or on a video? What happens to the front wheels? They start to shake and won't stop shaking until you slow the cart down. The shaking can be violent enough that it can make it harder to push the cart at the same speed. Shopping cart front wheels have a lot of positive caster. The more positive…

I have to apologize, Timothy. I was wrong about which way to go with the caster. The old boy straight away said "Increasing positive camber will make it worse, go to the low end of your caster spec and check your damper." without me saying much more than the words "four-by death wobble" and "caster". It was the old wandering Fords that they used to have to try to add positive caster to give the…

Echoing what the others have shared. If you can grab the long tie rod and twist the whole assembly more than a little bit, twisting one tie rod forward and the others back will tighten things up and help to stabilize.