It’s one of the more frightening experiences you’ll encounter behind the wheel. The vehicle is shaking so badly you think it’ll far apart and that you’re going to die. That’s why it’s called Death Wobble.
I hope you never experience it, but if you do, this column may help you survive with your wits intact (though you may still need a change of underwear).
Typically occurring between 45 and 55 mph, death wobble is caused by one or more problems with the front end or tires. That’s part of the problem. Drive train and suspension systems are so complex nowadays, it can be tough to pinpoint what caused the death wobble.
What to do if death wobble occurs
Before going into troubleshooting, we should review some of the steps to take in case you encounter death wobble and still need to get home.
The first step is to maintain your composure. Death wobble, as I mentioned above, is a terrifying experience. Slow down immediately and, if possible, pull off to the side of the road. Brake calipers will help slow down the death wobble too. Inspect your vehicle for any parts that are ready to fall off – tie rod ends, track bar, etc. You’re trying to determine if you can drive the vehicle home. If not, have it towed. Otherwise, you should be able to drive it, but keep your speed under 45 to prevent death wobble from reoccurring or try driving quickly thru the 45-55 trigger point. In most instances death wobble will not occur if you maintain a speed above the trigger point.
The tires deserve a quick check to see if you can solve the problem.
- Mud caked on the tire creates an unbalanced tire.
- Check that tire pressure is equal side to side on the front tires and that the tires are holding pressure. A loose valve stem can be leaking and is difficult to detect – so is a small stone wedged in the bead.
- Check for wheel weights that are missing.
- Check that the lug nuts are tight.
How to fix death wobble
Tie Rod & Track Bar Talk about complex! In a 4WD vehicle, a contributing factor is the lift kit and large tires. They throw off the caster angle and other elements, thereby making the vehicle more prone to death wobble. There are ways to get around that, but first we need to thoroughly inspect the tires and front end.
We’ll assume first that you’ve had the lift kit on for some time with no problems. If death wobble occurs, it means something’s not right but we don’t suspect caster initially.
Determining the cause of death wobble requires a thorough inspection of the suspension and drive train, as well as the front tires.
- Tires: Make sure there is no mud caked on them, especially on the inside. Mud causes a wheel to be unbalanced. If they’re relatively new and were balanced, you should be able to discount them. Also, check the tire pressure. Improper pressure side to side can cause a tire to wobble. Run through the same list above that you checked in the field
- Steering links: Start the vehicle, and have someone roll the steering wheel back and forth about ¼ turn continually while you watch each joint one by one. There shouldn’t be any movement on one side of the joint before the other moves.
- Look at each end of the track bar. There should be no movement in either. (The track bar is one of the top suspects. Not only may the bushing be worn but also the bolts and the hole maybe elongated. All will need to be repaired)
- Check tie rod ends at each wheel and at the pitman arm.
- Look at each of the adjustment joints on the drag link and tie rod. There should be no movement where the rods are treaded into the joint. A telltale sign is if the joint lifts up and down as you rotate the steering.
- Check the bolts that hold the steering gear box in place. Inspect the frame under the steering gear box for cracks.
- Check the toe in. With a lift kit and big tires, you generally have almost no difference from front to back. In the absence of real specs, I would set the toe in to a maximum of 1/16 in.
Inspect the tires. Are they mounted properly? Is there any problem with the tire beads? Spin balance each tire even if you just had it done recently.
- Check the caster angle. A lift kit tends to change the caster angle toward zero degrees, and sometimes even a positive angle position. Casters must be at a negative angle to operate properly. A minus 4 or 6 degree angle is generally required. Research the caster spec for your vehicle.
Dig deeper to solve a stubborn problem
- Inspect the axle U-joints. They could be worn and have some play in them.
- Check the wheel bearings. Lift each front wheel off the ground to check the wheel bearing. When you push and pull on the top and bottom of the tire you should have no play.
- Check the ball joints. With a floor jack lift each end of the axle up at the steering knuckle. Just as the tire leaves the ground, the steering knuckle and the ball joint should move together.
The next steps in eliminating death wobble
Centramatic Centramatic If you have replaced all the bad parts, balanced your tires and you’ve set the caster to the proper angle, there are a couple last-ditch steps you can take. The second one, especially, isn’t ideal, but it can at least allow you to drive your vehicle.
- Install Centramatic wheel balancers. They are designed to compensate for any anomalies in tire balance. http://centramatic.com
- Toe out the tires. Doing so will cause the tires to wear out prematurely, but if it works at least you’ll eliminate the wobble. I would suggest small changes- ½ to one turn at a time of toe out until it helps.
As you can see, there’s a lot to consider when confronted with death wobble. Chances are, though, you will eliminate it while going through the steps I outline above. Then you can get back to enjoying your trips!