Still on occasion violent wobble...

[reamer]

I have heard ( on the F-150 site) When Ford made the steering boxes, There were no matching berings and races inside the boxes, Just a bering and a machined area in the cast for a "race" as that area wears and becomes egged-shaped it's not "fixable" Enter companies like "Red Head" that say they machine out the cast iron area and install a race and bering.
This is why a "new" or "reconditioned" box from the auto stores still wobble "out of the box"
Reamer

 

[Kalex]

As always Paul I can't thank you enough for your insight. This board and the knowledge associated with it is truly inspiring. The tire shop I use doesn't have a road-force balance machine. I never tried what you said when my shocks were off so I had no clue the difference would be that noticeable. Interesting.

Unfortunately the stretch of road that caused this to happen again after months of being fine is not too close by so I am going to go out and just see what things overall feel like. My next step will then be moving front tire to back one side a time. As you can see I am desperately trying to avoid spending 1,200 plus on a new set of tires unless I can feel reasonably assured that's where the problem lies.

 

[Kalex]

Reamer, pardon my ignorance, but if from my cursory look at the box and frame while turning the steering wheel doesn't show anything out of the ordinary and when this wobble occurs I don't feel like I am getting undue play, vibration, etc...in the steering wheel/shaft itself would that matter? The shaking is violent until I slow quickly, but it is more the whole rig because of something occurring up front. I guess what I am trying to ask is would it not be more noticeable in the steering shaft/wheel if it was my steering box?

 

[DirtDonk]

Hah! I got "lucky" I guess and both times it happened on the Bronco (I've had many other vehicles that did it too) it was literally less than 100 yards from where I lived!
After the first time it happened I could repeat it each and every time at the very same places at the very same speed. Without fail.

By the time it happened with my Bronco I had already experienced it twice before, and basically knew it was the tires. But like you there was no way I wanted to spend $200 (Armstrong TruTracs were $49 a piece!) all at one time. So literally as a still very expensive experiment, but one I could do over time, I replaced each and every wear item on the front end. Including a brand new manual steering box that my local Ford dealer had in stock.
Oh, and it was the whopping sum of $175 bucks from the dealer!

Yes, I spent more money than I needed, and all the old stuff was the originally installed Ford stuff, but at about 75k miles or so (I think?) I figured it wouldn't hurt to replace them one by one. The only thing that made me happy was that the new steering box did feel way better than the old one. But the Death Wobble (I hadn't named it that yet though. That came a few years later) remained.

Of course, that's when it occurred to me (you know, after spending all that money needlessly) that it might be only one tire! So I literally drove back home, swapped the front tires to the rear, and voila! DW gone!
So I actually got to keep using those same tires for several more years. They were not that old.

And to keep this rambling story going... I remember another Bronco (don't think it was mine though) that again, with almost new tires, drove into a Taco Bell parking lot and cut the corner a little too tight and ran up the curb. Within minutes of leaving the parking lot, serious case of the DW's just like the others.
One small hit was all it took.

So with that in mind, do you by any chance remember hitting a curb, a rock, or a tree stump in a field, with this set of tires at any point?
It does not need an impact to happen, but it can certainly be due to those as well as just natural deterioration in a basically defective tire.

Paul

 

[Kalex]

Update....

So I think I found the culprit, finally. After moving tires around and all of the other stuff mentioned it still didn't "feel" right. I didn't replicate the wobble, but I knew it just wasn't right.

I decided to check underneath again with someone moving the steering wheel. This time a rougher surface and at angle so there was more resistance on the steering. I notice the track bar drop bracket moving. A weld on it has broken loose and it is flexing when under load.

It is possible that is not it, but I have a feeling that is the source of my problems. Thanks again for all of your consult. I really appreciate it.

 

[DirtDonk]

A loose, or flexing trackbar bracket will definitely let the vehicle follow grooves and wander all over the lane. Does not usually "cause" the wobbles, but we can't rule it out either.
It may even have been damaged from the wobbling, but only way to know for sure is when you finally get around to driving it over the same spot where it tried to kill you the last time.

Have you welded it back up yet? Or do you have to find someone to do it? Maybe even a muffler shop if they're willing to work on the heavier metal stuff like this.
Let us know how it feels afterwards.

Good luck!

Paul

 

[Kalex]

In my excitement of thinking I located this ghost that is driving me crazy I didn't even consider that it may have been broken by the 2 or 3 times the shaking occurred. I did go over the same stretch of road today, but it was prior to finding the broken weld. Due to traffic I could only go about 10 mph and nothing happened today.

I will need to locate someone to weld it as my welder is 2,500 miles away, lol. And I suck at it because I rarely if ever do it. I will report back as I trudge along in case any of this info. helps others. If this doesn't do it, I 'm replacing the tires. Thx Paul.

 

[svastano]

Just to add to what Paul mentioned. I had a 79 F150 that was lifted and had 39" Mickey Thompsons on it. The death wobble came almost immediately after the lift. All new bushings etc.I swapped the front tires to the back and it went away. I promptly took the tire back to where I purchased it and got a replacement. (they were not happy but they did it) Never had the death wobble again.

 

[sprdv1]

glad to hear it..

Update....

So I think I found the culprit, finally. After moving tires around and all of the other stuff mentioned it still didn't "feel" right. I didn't replicate the wobble, but I knew it just wasn't right.

I decided to check underneath again with someone moving the steering wheel. This time a rougher surface and at angle so there was more resistance on the steering. I notice the track bar drop bracket moving. A weld on it has broken loose and it is flexing when under load.

It is possible that is not it, but I have a feeling that is the source of my problems. Thanks again for all of your consult. I really appreciate it.

 

[sprdv1]

In my excitement of thinking I located this ghost that is driving me crazy I didn't even consider that it may have been broken by the 2 or 3 times the shaking occurred. I did go over the same stretch of road today, but it was prior to finding the broken weld. Due to traffic I could only go about 10 mph and nothing happened today.

I will need to locate someone to weld it as my welder is 2,500 miles away, lol. And I suck at it because I rarely if ever do it. I will report back as I trudge along in case any of this info. helps others. If this doesn't do it, I 'm replacing the tires. Thx Paul.

just be careful... especially if you don't got a cage