Death wobble. What’s the cause?
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Death wobble. What’s the cause?
Hi, I just about had the worst death wobble of my life the other day, and I was wondering if anyone could provide any info.
I was going about 40 mph when it happened, it was so bad that my head light fell off and was shattered on the ground, and my heater core hose flew off, and sprayed anti-freeze everywhere.
I checked the front axle to see if I could spot anything, found that there is bare metal on
1. My sway bar link bracket coming off the axle
2. A little around where the u joint goes on my 2-month old axle shaft and u joint ( I do not think that could even be the issue, as it’s all brand new. )
I have brand new hub bearings and brand new rotors, New ball joints, I lifted both tires in the air and neither one of them wobble.
Im thinking it could be the u joint on the other side where none of the bare metal is, that is all I can think of. What do you guys think? Before I do this hub tear down to find out I was wrong?
I was going about 40 mph when it happened, it was so bad that my head light fell off and was shattered on the ground, and my heater core hose flew off, and sprayed anti-freeze everywhere.
I checked the front axle to see if I could spot anything, found that there is bare metal on
1. My sway bar link bracket coming off the axle
2. A little around where the u joint goes on my 2-month old axle shaft and u joint ( I do not think that could even be the issue, as it’s all brand new. )
I have brand new hub bearings and brand new rotors, New ball joints, I lifted both tires in the air and neither one of them wobble.
Im thinking it could be the u joint on the other side where none of the bare metal is, that is all I can think of. What do you guys think? Before I do this hub tear down to find out I was wrong?
#2
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Year: 1995
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Death wobble is usually caused by the track bar. Either the mounting points cracked at the frame or axle, or the bushings are worn.
Could you post pictures of the "bare metal" you're referring to?
Did you check the sway bar bushing at the frame, it sounds like it's worn there. A new set of bushings is like $10-15, so if the bushings are bad, definitely replace them.
Double check the torque on the hub bolts. I believe they're 80 ft/lbs IIRC.
Could you post pictures of the "bare metal" you're referring to?
Did you check the sway bar bushing at the frame, it sounds like it's worn there. A new set of bushings is like $10-15, so if the bushings are bad, definitely replace them.
Double check the torque on the hub bolts. I believe they're 80 ft/lbs IIRC.
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Death wobble is usually caused by the track bar. Either the mounting points cracked at the frame or axle, or the bushings are worn.
Could you post pictures of the "bare metal" you're referring to?
Did you check the sway bar bushing at the frame, it sounds like it's worn there. A new set of bushings is like $10-15, so if the bushings are bad, definitely replace them.
Double check the torque on the hub bolts. I believe they're 80 ft/lbs IIRC.
Could you post pictures of the "bare metal" you're referring to?
Did you check the sway bar bushing at the frame, it sounds like it's worn there. A new set of bushings is like $10-15, so if the bushings are bad, definitely replace them.
Double check the torque on the hub bolts. I believe they're 80 ft/lbs IIRC.
Just need to crawl under and turn the wheel and see what flops around.
#4
CF Veteran
Anything that allows the axle to oscillate laterally (left to right) can contribute to death wobble. Several components work together to keep lateral motion of the axle minimized, and under certain thresholds. Key among these are the track bar, upper and lower control arms (and their bushings), and the steering gear. The track bar is the primary component responsible for lateral location of the axle. So any deficiency in its function can contribute to death wobble. Any play at either connection end of the track bar is cause for concern. Whether it be loose fasteners, worn out/damaged brackets, etc, it is worth addressing. The control arms provide a 2nd line of defense against uncontrolled lateral motion in the axle. Their main function is vertical and longitudinal location of the axle, but then they are tightened properly, and their bushings are in good shape they also help to stabilize lateral movement in the axle. Finally, the steering gear. This is the component that almost always gets ignored from lists of things to check when death wobble is observed. While the steering gear is not responsible for locating the axle, its primary contribution to minimizing the onset of death wobble is that it provides hydraulic damping to sudden movements of the steering components. It can help dampen a lateral oscillation in the axle before it becomes resonant and destructive. Although a steering damper is not usually considered a root cause for death wobble, it also can help dampen sudden jolts to the steering system. So having a properly functioning steering damper is worth the trouble.
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Thank you all for replies!
When my buddy comes around later I will have him turn the wheel for me, I was kinda presuming it was the trackbar from the start, here are some pictures of the bare metal.
#6
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Bad ujoints and swaybar bushings wouldn't cause death wobble. As said above the main cause of death wobble is bad or worn track bar bushings, control arm bushings, tie rods, ball joints, steering gear, or alignment is off.
#7
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If you had violent shaking that caused components to come apart, you have something that you should be able to find pretty easily. Get your buddy to turn the wheel and it should be obvious.
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