Would like opinion about death wobble. Here is the chronological run down...



I have a 2018 F250 super. In March 2020 I put front leveling kit and 35s on the truck. The leveling kit was the spring spacers and shock extensions. Long story short, I failed to get alignment after install. In May 15, 2023 (this year) I added the track bar extension / relocation bracket and sway bar extensions and removed the lower spring spacers and put the top of spring spacers on. I also upgraded shocks and a new steering damper. Truck drove fine. On June 13 I had the truck alignment performed by Ford. Within a few days after the alignment I started getting the death wobble. I took it back to ford and they claimed it was the aftermarket damper that I put on a month before they did the alignment. In September they put a new FoMoCo damper on. After a few days now the death wobble is actually worse! I called Ford and they are saying it could be something loose or the aftermarket products on the truck (even though the wobble never started until after they did the alignment). What are your thoughts? Could it be related to the alignment? Could it be the aftermarket parts? Could it be because I never got the truck aligned originally and it is a tire issue? Thank you for your thoughts...

 

Well with your mods the first thing you need is a good strong aftermarket track bar. Then start over on your alignment specs.

 

You might want to try a shop that specializes in alignments, and not the Ford dealership. An independent alignment shop can customize the alignment to your lift (with camber and caster adjustments that the Ford dealership is prohibited from performing; they just follow factory specs).

Also, there are aftermarket bushings that allow for more adjustment (such as the ones below). I have a leveling lift on mine, and didn't require these. But, sounds like you might.

 

From the factory there isn't much Caster to prevent worn part DW. Adding a lift then decreases the Caster even more. Think shopping cart wheels. Thats what your truck is doing. The truck needs at least 4* Caster to help fight the wobble.


When the top of the spindle is at or near zero degrees, anything from tires to worn parts can set up the wheels to shake side to side. the further forward that top is towards the front of the vehicle the more likely the tires will shake. Moving that top further rearwards tightens up the tires so they are less likely to wobble. They track straighter and return to center much faster to. The drawback is that it takes more effort to turn the wheels, and puts more stress on the steering gear, which is probably why Ford has the minimum Caster settings.

A pair of these should help

 

one link is for a 2.3 degree and the other is for a 2.6 degree. I assume I need the same degree on both sides but is there a preference?

 

the link is for a 2.5 degree. I assume same degree for both sides. You noted in your first comment that it needed at least a 4* caster?

 

(deleted, after double-checking my mistaken facts)

Edit: I originally posted and thought that the bushings linked earlier would allow for up to an additional 2 to 2.5 degrees of adjustment. That might still be the case, but will have to confirm...

Additional Edit: Located the following bushing, which allows both caster and camber adjustment. Much better alternative, IMO:


Instruction sheet (posted from one of the reviewers at Amazon):
As can be seen from the chart in the second image, it appears that the adjustment range is still ~+-2.5 degrees, however.

 

Those caster shims linked would be used on different sides.. The 2.3 would go on the drivers side, 2.6 passenger side. Most go with SPC but maybe those Moog parts are the same.
The style of adjustment bushings in the last post shouldn't be necessary unless there is something strange going on with your camber. Do you have the alignment print out from Ford?

 

I do have the alignment print out. Thank you for all that information...

 

Thank you for all this information!

 

Those are what I used on my 2012 F350 to get nearly 5* Caster. IF you look at the ball joint end, there as barely any metal left while keeping the nut end centered. Factory shims are 0*, the caster is built into the axle itself. So if the factory caster is 2.5*, the 2.5* caster I linked will bring it to a total of 5*.

If you have the print out, then get shims that add up to at least 4*, IOW if the current Caster is 2*, get a 2* shim.

 

According to the alignment they did in July my caster is currently 1.1degree on the left front and 1.6 degree on the right side. What replacement caster do you guys think I should go with?

 

Looking at my alignment paper from July the caster degrees are currently 1.1* on the left and 1.6 degree on the right. Still think I should go 2.3 and 2.6?

 

At the very least, that gets it over 3*.

1 degree is barely angled and thats a great way to get the front tires to wobble. The ones I linked brought mine to nearly 5*, but I don't know what it was to begin with and it was stock height.

 

Okay I'm not knowledgeable in death wobble problems and solutions but I remembered a post here that referenced a company that seemed to have a lot of info on this... just found it, finally.

Here's the post here.

Here's the link to the death wobble page on their website here. Alignment specs...

Just FYI.