I just replaced my front leaf springs on my 78 f250 along with doing a complete dana 44 front end rebuild kit. I took it for a test drive and wow does it ever drive better and handle better. However, once in awhile around 40 to 45 mph the truck starts to death wobble. I am not sure what is causing this as i also have relatively new shocks in in all 4 corners that i know are operational. The steering stabilizer shock is old and i doubt it works anymore which could be the cause along with my alignment being out of wack. I also have a few ball joints in the steering linkages to replace aswell which i doubt has much to do with it. Before i did this work to my truck it used to have a bounce (not a wobble) around those speeds i mentioned earlier. I replaced my front leafs with a heavy duty springs they have 3 springs and are thicker than OE (General Spring if you guys are looking for some that are at a good price) would going to a stiff spring cause death wobble which also ended up leveling my truck? I have checked 2 or 3 times to make sure everything is tight down there and everything seems to be.

What have you guys done to fix the death wobble? my plan is to get the stabilizer shock (Bilstein) and install my new new tires which of course id get an alignment during. What else would you guys try? thanks!


The Dana 44 rebuild kit is offered from Jeffs Bronco Graveyard. It is a fantastic deal in the neighborhood of 600 dollars and comes with a ton of new parts to put on. if i bought everything seperate it would have been 1000 plus dollars. thought id let you all know.

 

You already answered your own question....anytime suspension lift/steering geometry/tire size changes are made you need to be dead nuts sure all your i's are dotted and all your t's are crossed, otherwise vibration aka "death wobble" will curse you til the end.

All ball joints/king pins must be tight! All steering linkage must be tight! the gear box must be tight! Any slop in the system will be amplified x10 at the steering wheel. Steering stabilizers can help to mask any issues, but they do not correct them.

 

X2 with above. Fix any ball joints or steering linkage that are loose before you waste your money on an alignment. I'm not saying the alignment isn't part of the problem, but you'll just have to pay to do it over again when you replace stuff afterwards because it is still wobbling due to the previously mentioned worn parts. Also, check all of your bushings too (track bar, sway bar, C bushings, and radius arm). They get forgotten and can have a large part in death wobble too. Polyurethane is better, but just make sure they are not worn out or severely cracked. New tires might help or at least have the old ones balanced, but do them after the alignment to save the wear on them. Steering stabilizer is not a bad idea, but agree that it is not causing the wobble, just not helping to hide it very well.

 

Agree fix everything loose first. Then alignment. For stability, you want some positive caster. The new springs could have changed caster. Offset knuckle bushings and/or tapered spring shims are needed to adjust caster.

 

The one caveat I would add is if you're running oversized tires (35" and bigger) make sure they are properly balanced. Many shops do no not have the equipment to properly balance tires over 37" but they will tell you they're "OK".....well, "OK" is not good enough.

If you still have "death wobble" after all the fixes you can be assured it's the tire (improper) balance at the root of your issues.

 

 

 

jack up one side at a time take off tire, check for play turning knuckle left to right. This should show slop in steer linkages. Next use a breaker bar long as possible stick it in the rotor vent area on top, push on it if movement could be wheel bearings, ball joints, etc. keep looking for points that have movement on one side and not the other side of component.
New leaf springs cam with bushings installed? bolt shanks had snug fit thru sleeves? what about top shackle bushing new??

 

Best thing to do is to lay underneath and watch as someone turns the steering. If that don't show you what's going on, then have same person push back and forth on the side of the truck. If it has wobble, the culprit should be obvious.

 

Comment on alignment (after everything is tight).

Positive caster and toe in promote stability.

Caster set on high side of factory spec positive (or a bit more positive) and toe in to factory specs should do it.

 

Thanks for all the replies. I will have to check some of that stuff out. It shouldnt be wheel bearings or any of that since all of that is new in the front end but who knows. Im going to get new balljoints for the steering linkage, the shock for the stabilizer, and when my tires come in an alignment and wheel balance. Hopefully between all of these it will fix the issue. If not ill be back asking more questions. Thanks again

 

You will eventually get it sorted out, it's just a process of elimination. Even the slightest bit of slop anywhere in the steering linkage is magnified by the time you feel it at the steering wheel.

 

Sounds like you already had the makings of the DDW's (dreaded death wobbles) before the lift. And lifting just caused things to go over the edge, as the others have said.
Caster makes a big difference, as does anything loose. On Broncos and F150's a loose trackbar bolt can really add to the mess. Unfortunately a Death Wobble happening will also loosen all of those things up even more!

But I'll make a pronouncement here and now (like I am the be all, end all and know-it-all of all things) and I'm going to tell you that it's your tires.
Not to take away from any of the other things that have been said. Because they all come into play here. But literally the ONLY thing that will actually CAUSE a Death Wobble even is a tire, or tires. Everything else can help bring it to the fore, but nothing else but a tire can cause it.

So the first thing I suggest is rotating the tires. Do you do this yourself, or have it done at a shop? I'm assuming you can do it since you installed a suspension lift, so that's what I recommend first. One side at a time, front to rear. Just to see if anything changes. If not, do the other side.
Then I'd have the tires balanced. Road Force balancing if you can, but anything is better than a bad balance.

But in my experience, bad balance usually leads to shimmy. Yeah, it can be a bad shimmy even, but usually a full on death-wobble comes from a bad tire or tires. Something inside usually, but the tread being worn in just the right way can lead to the onset as well with the right conditions. A deteriorating belt or layer of tire inside, or a damaged sidewall is often the culprit. For this reason it can start on a passenger front tire too, because those are the most often beaten on curbs and unseen rocks and such. But those aren't the only circumstances, so there's no guarantee.
And if you're lucky, it's only one tire anyway, and once you rotate it to the back the DW's will go away completely. If it's more than two however (I've had three and four before), you might have new tires in your very near future.

The larger the tire, and the more negatively offset the wheel, the more likely a tire is to have an advantage in starting this problem. There's just more leverage against the steering and suspension and at some point they just can't handle it and the oscillations that are normally kept at bay get out of hand and cause the wobble. And your 40-45 mph repeatability is a classic tire death wobble event.

So that's my suggestion and I'm sticking to it. I've had, or close friends have had the Death Wobble on four separate occasions. Other acquaintances have had them many more times, and in all cases it was at least one tire.
My first time was on mom's '67 Buick Wildcat in 1970. In that case, the old-timer at the alignment shop said he guaranteed it was a tire, and had it changed. I don't remember how he determined which one it was, but he nailed it.
My second time was my '71 Bronco in about '78. As an experiment, and because I wanted to change out a bunch of stuff anyway, I changed literally everything that could be changed in the front end. Including ball-joints, u-joints, trackbar bushings, rod ends and even a brand new steering box I bought from the Ford dealer for $175 bucks (those were the good old days!) and nothing got rid of the problem. I could repeat it consistently on the same bump, on the same bit of road near my place if I hit it right at 35 mph. It would come on like a jackhammer and not stop until I got back down to about 10 to 15 mph. Every time.
I rotated the right front Armstrong Tru-Trac to the rear and the wobble was gone forever. Used those tires until they had no tread and it never came back.

So in case you hadn't guessed, my vote is a tire.
The good news is that if it's a tire or two, rotating them to the back works out to be much less expensive than replacing all the other parts it could be!

Good luck.

Paul

 

Paul, you were right on the money. My tores were shot. I was waiting on a new set to come i the mail. The front tires tread was almost completely worn down... dont give me **** haha. Must be when i did stuff to the front end it pushed it over the.limit. i got my 4 new tires mounted,balanced, and aligned and it went away thankfully. I did the lifetime alignment at firestone. Totally worth it if you guys have a vehicle you plan on keeping for awhile/forever. I know my dent isnt going anywhere in the forseeable future.

 

Whew! Crisis of worn out parts averted! Yeah, tired old tires are hard to make work right ever again once they've gone over to the dark side. Glad you had new ones on the way so it went away even quicker.
Enjoy the new street manners.

Do they rotate the tires in that alignment warranty too? Or is that separate?

Paul