Saga continues. As my dealer waits on direction from Ford, I was in traffic today at 60 miles per, truck began shaking worse than ever, I could not steer right or left due to the violent shaking, applying brake pressure only made it worse, wasn't until the truck got down to 10mph that the shaking stopped. My service department thinks there may have been a lot of bad parts, so we will see.

 

So as has been questioned, have the tires been replaced?

 

You “MAY” have to fix this yourself, or trade it off. You need to systematically approach this. I would start by first fully understanding how everything related to your steering/suspension system works. What does what. You may need to get under your truck yourself, and have a partner move the steering wheel back and forth in short strokes, watching every connection, ball joint, tie rod end, pitman arm, steering box, etc for ANY play or movement that should not be there, Any thing flexing that should not be. Generally speaking, the tracbar is the first place I look for any movement, if one end has movement, it can allow the axle to shift side to side, resulting in the DW. @17 Oaks gave a good rundown of parts to check. You might send him a PM for a more detailed instruction about how to deal with this. It IS fixable, but you have to go at it systematically.

 

The TSB that I was shown, indicates that Ford knows there is an issue with certain SD trucks. The TSB mentions all items in the steering system. It is just a matter of getting as fix. I keep seeing the suggestion of putting aftermarket parts on to correct the problem. Why? I have a stock F250SD 4X, bought it new with the expectation that I was buying a safe vehicle, why should I spend extra dollars to fix something Ford should have right to begin with. I do like the truck its pretty when it is sitting.

 

Ford got it right just like all the other auto makers they to got it right. So don’t blame Ford it’s not their fault!
Win
I have had it occur on my motorcycle my Corvette and most of the cars I drove over a long period of time.

Here is your problem newtons thought third law of motion.

Third law:When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.

this is exactly what death wobble is you mitigate it with steering stabilizer.

in addition you have to inspect and replace or adjust or tighten all of the components.

 

^^^^^^^^^^^^^^^ This.

There aren’t many people that truly understand DW, nor how to fix it correctly. I understand your feeling like it should be on Ford to remedy this, so with that, you might need to find a different Ford shop that has somebody that knows what they are doing and go there. Also, once DW happens, it can and will hammer on the good parts and destroy them also, making more stuff needing replaced.
Most dealership shops just have “parts replacers” instead of mechanics. They look in the book, book says replace such and such part, so they replace said part and sent vehicle out the door without having a clue as to cause and effect.

 

So I read the DW posts with great interest as I live in NJ and often find myself in bumper to bumper traffic going 90 MPH with dump trucks and fools putting on makup etc 3 inches away from my fenders... I have a 2019 250 Lariat with 20" wheels, the stock Michelins, and 5500 miles on the clock. I do feel some whacking through the steering wheel on certain kinds of bumps. All in all I think she rides nicely for a 3/4 ton solid axle truck. But I find myself gripping the wheel as I approach bridges on the highway in anticipation of something crazy happening...Ive driven and raced pretty much anything that drives so Im confident in my ability to just deal. But I wouldnt want my wife experiencing the DW on the highway.
I have a few observation for comment.
I have a 2017 F-450 mason dump at work. Not much highway but Ive had it on state roads and interstate at highway speeds plenty of times. I get zero bump steer. over bumps or bridges...really I get no feed back at all through the wheel over bumps... I know its the "wide track" but it seems to me wider trac would put more leverage on the steering. The 450 has the stock Conti tires and usually close to max air pressure. The 450 rides equal to and in some cases better than the 250. Im running the Michelins at 60 front 55 rear commuting empty.
Does anyone know if the 450 has a substantially heavier stabilizer? I didnt plan on changing expensive parts out so early. But most guys are changing tires/shocks/stabilizers almost right away. That kind of pisses me off after spending in the 50s for a beautiful HD truck. How many retired spouses are driving 5th wheels through mountains at highway speeds?
Is there a build up of symptoms? or does your truck just suddenly go from normal to haywire over one bump?
I used to get something similar from old big trucks and it was usually king pins or other spring mounts being worn beyond serviceable.
I like to keep the DW posts up on the first page to keep the dialog going.

 

To give you a couple of pictures for a visual. On my Jeep I have a 37-12.5-17 Goodyear MT/R’s with Staun internal beadlocks, making for a heavy tire and wheel assembly. I had built up all components with heavy duty parts......tie rod, tie rod ends, drag ling, ball joints, tracbar, etc. Everything.
After a while ......yup.....death wobble. I was under it many times. Looking for just what it could possibly be. Road force balance all tires. Install good steering stabilizer, etc. Adjusting toe in, caster, tire pressures, etc. I found that by running at least 42 PSI in the front tires, there was no DW most of the time, but it would still occur at certain speeds if a bump was hit just right. Study things some more. On the heavy duty tracbar, there is a heim joint where it attaches to the axle, and there was a pliable rubber bushing where it attaches to the frame.

When I was under the rig, having someone work the steering wheel, I could not see any movement there at all. But, since I have a minimal understanding of DW, and minimal understanding of Newton’s third law as per @17 Oaks stated above, I thought there is a possibility of something I can not see.
When it comes to dealing with DW, the obvious is not always obvious. So I went to work and built a solid bushing to take the place of the above rubber bushing.

Before installing this bushing, I made sure the mounting holes in the frame were round (not egged out), rounded up a 9/16” grade 8 bolt, fit the bolt snugly into the inner bushing, fit the outer bushing into the tracbar and re-installed the tracbar. Went out and went for a drive......NO MORE DW!!!!!!!!!!!
After all this was done, NOW I went ahead and install a FOX steering stabilizer to help it drive even better. I have driven across cattle guards, hit bumps, done everything I can to get it to wobble and it is all good.

I have showed you all this to demonstrate that it could be just one component that was sub-standard when it left the factory, but it takes somebody to understand what to look for to figure it out. Maybe, in my ordeal, the compound used to make the bushing was not up to standard, I don’t know.
It could be a certain combination of little things. These are all man made, and subject to flaws. Sorry you got one that is flawed.

PS. Just so I am not mis-understood in the picture of the solid bushing, the inner is slid half way out for a better visual.

 

If an amateur can fix it, Ford can fix it.
They need to be forced to do it.
That’s what government regulation
is supposed to do.

 

Anyone who has ever experienced true death wobble knows it’s way more pronounced than what tires can effect. It would be like driving on a blowout. Now tires can trigger it but it’s not the cause. OP, it’s the track bar. That is the only solid transfer between axle and Frame. Replacing the lower track bar ball joint is the solution 95% of the time. The other 5% it’s the upper track bar bushing. Make sure they replace both since you have there attention. I wouldn’t keep driving the truck that violent shaking will take the whole front end out in short order.

 

Maybe our fantastic congress can outlaw Newton’s Third Law!!!!!!!!!!!!!!! Isn’t that what government regulation does.......make laws and ban others!!!!!!!!!

 

Its always the track bar.

 

slangvel, I realize you may still be under warranty, but don't go to the dealer any more for this. Find a suspension specialty shop - they will usually advertise handling everything from cars to Class 8 trucks/buses. My 96 Ram had significant DW until Hackensack Spring in Hackenack NJ got hold of it at 6 years old (I grew up in the next town and always knew of them). When they were finished, the truck drove straighter and tighter than when it was brand new. Didn't have DW again until several years later after I hit some debris in the road late at night - the left front tire went over the chunk and caused some excessive play in the front end... obviously I knew the cause that time.

 

@slangvel What are your front tire pressures, typically?

 

60psi Nitrogen With the nitrogen I have constant pressure no variance as with air.