Death Wobble

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Introduction

"Death Wobble" is a phenomenon where the steering wheel shakes, usually at around 35-45 mph (60-80 km/h).

The wobble ranges from a slight shake to a violent steering wheel shake that can be felt through the whole truck. It can be so severe that it forces you to either slow down below the wobble speed range (if you are a coward) or speed up above the wobble speed range (if you are brave).


With big aggressive mud terrain tyres, or retreaded (remoulded) tyres, a little steering wheel shake may have to be lived with.


The Video

The following two videos vividly portray a case of severe death wobble in a Jimny.


Experience inside the cabin:


What actually happens in the suspension:


Theory behind the phenomenon of "death wobble"

"Death wobble" is a known "genetic trait" of all vehicles with have dependent front suspension (typically solid front axle - SFA).

Note: The elements which make a suspension system are all the various rods, arms, joints, bushes, bearings and mounts, as well as the wheels (rims and tyres) themselves. The wheels are often the overlooked element.

Dependent suspension means that the left and right side of the axle are connected, and therefore any dynamics occurring on one side affect the dynamics occurring on the opposite side, and vice versa.

That (among other characteristics) makes dependent suspensions great for all-terrain duty. However, the unfortunate negative effect of their "dependness" is that any disbalance or "play" on either side of the suspension will transmit or "resonate" to the other side, and vice versa.

Since suspension is a system of connected dynamic elements, the vibration happening on one side due to disbalance or play will induce a vibrational resonance with the other side at a certain speed range. The resonance will make the entire suspension system vibrate, which will then affect the entire vehicle.

The speed at which the resonance occurs depends on many factors, but it can be rougly said that the speed is directly proportional to the size (length and width) of the vehicle, and the size of the wheels.


In a summary, dependent front suspensions are rather sensitive to any disbalance or play.


Most all-terrain vehicle models with SFA are significantly larger than Jimny (Land Rover Defender, Jeep Cherokee, Nissan Patrol, Toyota Land Cruiser 80, etc.) and they use much larger wheels.

Therefore, the speed range where the vibration resonance in their front suspension would occur would probably be (guessing) in the range 130-180 km/h. Since those vehicles are rarely if ever driven that fast, 99% of their owners will not experience death wobble even if their suspension components are quite worn.

Since Jimny and Samurai are much smaller, they develop vibration resonance in the most "inconvenient" speed range of 60-80 km/h.

With (a stock) Jeep Wrangler, which is slightly larger, the death wobble has been reported to typically occur between 80 and 100 km/h.


General procedure of solving death wobble

The disbalance or play can even be caused by trivial causes such as dirt (like mud deposits on rims), or rusty contact surfaces between the rims and the wheel hub for example. It is also possible that a balancing weight on a rim has fallen off in the meantime, so the wheel has lost its balance.


The problem need systematic approach to solve, as it can be be very expensive and time consuming to replace parts on random guessing.

The approach is to perform the simplest, cheapest or most common fixes or replacements first, and advance toward more expensive or complicated ones if necessary.


The proposed order of solution is this:

  1. Clean the rims and wheel hubs where they meed each other, and also clean the mating surfaces of disc brakes and wheel hubs.
  2. Check if the tyres are warped. If they are, buy new tyres. That's a good thing to do anyway, and a chance to treat yourself with something new.
  3. Check if the rims are warped. If they are, have them repaired (straightened) in a specialist shop, or buy other known good rims
  4. Balance the wheels in a well equipped workshop.
  5. Replace tie rod ends if worn.
  6. Perform professional wheel alignment in a well equipped workshop (wheel alignment has to be performed anyway after any tie rod end change).
  7. Preventively replace front radius arm bushes which connect them with the chassis, and replace any worn radius arm bushes.
  8. Replace worn panhard rod bushes.
  9. Replace kingpin bearings (the bearings on which the front wheels turn left-right)
  10. Replace kingpins or insert custom shims under the kingpins
  11. Replace worn steering knuckle swivel seals
  12. Replace front wheel bearings.


Other considerations

  1. Tyre pressures
  2. Warped front disc brakes
  3. Paranormal issues


Detailed remarks about each step in solving death wobble

1. Cleanliness

There is not much to say about this step, except that a few people (for example forum user Rockwatt) have confirmed that the dirt and rust was the sole cause of their death wobble. Being tidy and doing a good cleaning (using wire brushes and some chemicals) saved them a lot of time and money. So why not try that first!?

  1. So, each time when you rotate or change the wheels, preventively check if the rims and wheel hubs are clean, especially where they meet each other. If not, clean them.
  2. If you have the death wobble, clean the mating surfaces of disc brakes and wheel hubs.
  3. This cleanliness extends to the sealant used in rebuilding the wheel hub. Do not use too much on the kingpins themselves as this creates a layer when prevents the kingpin from seating correctly. Also ensure that the kingpin itself is rust free.

Also, it has been confirmed several times that "temporary" death wobble develops whenever rims get filled with mud or snow. As soon as you wash them good, the death wobble is gone. So be tidy!


2. Warped (distorted) tyres

Any good tyre professional can check this on a good machine. Some slight wobble in tyres can be expected, but a significant one can be the problem. Tyres can develop wobbles from abuse and from age, or simply because of low quality.

If you suspect that the tyres' wobbliness is the cause of your death wobble, then solving the death wobble might be just the right excuse that you have been waiting for to buy those new flashy AT tyres that you have been wishing for a long time!

Beware that, in general terms, the more extreme the tyre is, the more difficult it is to balance properly, and there is more of a chance to be wobbly from the factory. So, don't use MT tyres if you want to minimize your chances of living with death wobble.

With retreaded (remoulded) tyres, "all bets are off". You get what you get. They are essentially tyre zombies - corpses which have been brought back to life like a Frankenstein. They are notorious for being hard or impossible to balance, and for each of them in a set to vary widely in characteristics.

Death wobble can also be caused by using significantly larger tyres than stock size, because that significantly alters the working parameters of the suspension system (remember - wheels are the part of the suspension!). If you opt for large tyres, you are dancing with the devil on his podium.


3. Bent (distorted) wheel rims

Death wobble can be caused by bent (wobbly) wheel rims, either steel or alloy. This was the sole cause of death wobble for BigJimny forum user Bosanek.

In many cases the rim distortions are not visible even to the trained eye, so special machinery is needed for measurement.

Some better equipped tyre service workshops do have machinery for detecting and also straightening bents and distortions in steel and alloy rims. Bosanek solved his death wobble by having his alloy rims repaired in this manner.

Therefore, whenever you go to balance your wheels, you should go to a well equipped and reputable tyre workshop, and ask them to check your rims for distortions as well, and repair them if found.

It is best to repair warped rims at the same time when changing or buying new tyres.


4. Wheel Balancing

If your tyres and rims are not warped, then balance your wheels again (even if you had done recently), but this time in a well reputed and well equipped workshop.

After the balancing is complete, note where and how many balancing weights are placed on each wheel. If the death wobble occurs later on, check if any of the balance weights are missing (they can fall off when driving off road). That way you might instantly find the cause of your issues.


In the UK, the "O2" branded Jimnys with the 3-spoke alloy wheels seem to suffer more from balancing issues. If you have the 3-spoke "O2" alloy wheels, try taking these wheels off and rotating them around one stud position.


"Road simulation" balancing process

It would be best if you could perform the wheel balancing on a "road simulation" balancing machine. Contrary to most ordinary balancing machines, which do the measurements while spinning the wheel in mid-air, these machines have heavy rollers which press onto the tyre while they rotate the wheel and measuring disbalance, simulating on-road driving pressure.

The point is that the wheel as a system behaves differently when spinning under load (as like when mounted on a car and driving on a road) as opposed to ideal conditions when spinning in mid-air. Therefore, these "road simulation" machines attempt to make as much as close to realistic measurements, to achieve the correct balancing.

Example of such a machine is "Hunter RoadForce" wheel balancer.

Just beware that most of those machines can also work in "ordinary" (mid-air) mode without applying the rollers. So you must double-check with the personnel in the workshop to make sure that they will use the rollers with your wheels. Sometimes they don't want to use the rollers, especially with AT and MT tyres, as it complicates their work and takes more of their time.


Balancing beads

Using balancing beads instead of balancing weights might be a better solution, especially if you have chunky off-road tyres or remoulded (retreaded) tyres.

Balancing beads are small, precisely made pellets which are placed inside the tyre (at the time of mounting it on the rim) and they dynamically balance the wheel as it rotates. Whenever you start from a standstill, it takes a few wheel turns for the beads to spread inside, and after that they dynamically adapt and balance the wheel until you stop again.

Beads are sort of "alternative medicine" compared to conventional balancing weights, but if it cures, then it's good!


5. Track Rod Ends / Steering Rod Ends

Worn track rod (steering rod, tie rod) ends will have slop in them and cause death wobble.

Jimny has four steering rod ends, so it isn't a surprise when one gets worn.

There is a guide on the main Big Jimny website on how to change them: [1]

You can buy new ones from the BigJimny Shop, which sells both (OEM) ones and aftermarket made ones.

You need one standard thread and one reverse thread per rod – so 2 of each for the whole car.


Be aware that it is necessary to perform professional wheel alignment (https://en.wikipedia.org/wiki/Wheel_alignment) after any tie rod end change.

Considering that obligatory work and expense after each tie rod end change, and considering the fact that genuine Suzuki (OEM) tie rod ends are the most durable (especially when used in heavy-duty), it is recommended to use OEM tie rod ends. They cost more, but they pay off more multiple ways.


P.S.: It is also possible to reduce some steering play by adjusting the steering box. Beware that some play in the steering box is normal, as written in official Suzuki's service manual. Note that adjusting the steering box should be used with extreme caution, as if you overtighten it or overslack it too much, it can wear prematurely, and the steering box is giga mega uber super duper ridiculously expensive.


6. Wheel alignment

As already said, it is necessary to perform professional wheel alignment (https://en.wikipedia.org/wiki/Wheel_alignment) after any tie rod end change.

However, doing it just on itself might be a good idea to cheaply and quickly resolve death wobble (and solve some other issues along the way), as the alignment can get out of order if you hit hard a big bump, hole or sidewalk, or if you drive hard off road. Misalignment could cause suspension disabalance.

It is important to do the wheel alignment in a reputable workshop with advanced equipment. For example, Hunter makes advanced and proven wheel alignment machines.


7. Radius Arm / Trailing Arm Bushes

Mainly the front arm bushes are a contributor / cause of death wobble but the rears could sent movement through the car. They can also be an MOT failure if bad enough.

The most common bush to give problems is the one on the chassis end of the front arms.


There is a guide on how to change them on the main Big Jimny website: [[2]


Several aftermarket radius arm bushes are available, both rubber and polyurethane. ADL Blueprint is one of the aftermarket manufacturers for example. Aftermarket rubber ones cost much less than genuine Suzuki bushes, but there are experiences that they do not last as long.

More so, Suzuki has released revised radius arm to chassis bushes around 2007-2008 specifically to cure death wobble, and those bushes are installed from the factory in all Jimnys since cca 2007-2008. The part number of the revised Suzuki radius arm to chassis bushes is 46213-76J00 (the part number of the old and deprecated bushes is 46213-65D01). They fit either front and rear radius arms on the connection with the chassis, and one is used per each radius arm.

Conclusion: It is most preferable to use genuine Suzuki bushes, and revised ones for the position of the connection with the chassis.


Note about polyurethane bushes:
Alternatively, slightly more expensive in some cases but easier to fit are polyurethane bushes. The best come from Super Pro and can be bought from a number of places – Off Road Armoury, Bits4Vits, Jimnybits, KAP Suzuki. Polyurethane bushes sometimes do not have slots cut in them that the original Suzuki ones have, these can mean a firmer ride on the road. However, if you are battling death wobble and are tired of experimenting, then buy the OEM bushes.


8. Panhard Rod Bushes

Panhard rod bushes are there to restrict axle movement. Therefore, any extra movement can translate to death wobble.

Unfortunately, Suzuki does not sell panhard rod bushes separately. They sell only buy the entire panhard rod with bushes already installed.

The only aftermarket manufacturer which sells rubber panhard rod bushes for Jimny is Febest.

You can buy replacement polyurethane bushes from the Big Jimny Shop : [3]


Beware that the panhard rod bush mounting holes can wear to an "oval" shape allowing the rod to move.


9. King Pin Bearings

Front wheels rotate left-right on kingpin bearings. Jimny uses four kingpin bearings, two per each front wheel.

For some reason, the Jimny King Pin Bearings don’t last as long as we would like them to and they are the main reported cause of death wobble on this forum.


You can check for wear in the king pin bearings by jacking the car up, putting an axle stand under the axle on the side you are working on and trying to move the wheel with a hand at 12 o’clock and a hand at 6 o’clock. If you feel any play you can help confirm its the kingpin bearings by getting an assistant to press the brakes whilst you are doing it. If the play can still be felt, then its the kingpin bearings. If it disappears then look at the wheel bearings.

Transmission oil on your swivels is a good indication that the kingpin bearings have failed and have caused the axle tube oil seal (halfaxle oil seal) to have failed by the excess movement. A halfaxle oil seal comes with the bearings when bought from the Big Jimny Shop – replace it.


Spanner Icon.pngHow to change your Kingpin Bearings



The bearing manufacturer for Suzuki was/still is KOYO. If you buy your king pin bearings from the Bigjimny Shop you will at the time of writing get KOYO’s, so you know they are the correct spec. here

Another good kingpin bearings are from manufacturer SKF - bearing model "30302 J2".


10. Shim or replace Kingpins

Each kingpin bearing is tightly connected with a kingpin. Kingpin's purpose is to securely hold the wheel knuckle assembly to the axle swivel, while allowing it to freely rotate on the pair of kingpin bearings. It's a "tightly tuned" system.

If the kingpin is worn, rusty, not seated properly or provides insufficient or excessive load on the kingpin bearing during operation, that can either cause vibrations, or premature wear of the kingpin or the kingpin bearing, which will again cause vibrations after a while.


The pre-load on the kingpin bearings is set from the factory, and if replaced properly with all the correct torque settings etc, in theory the pre-load should be right and there should be no death wobble after replacement (if bearings were or only cause of it).

However, it appears that the theory can take a "bit of a battering" on this occasion, so Suzuki brought out some shims to add to the king pin in an effort to increase the pre-load on the bearing. Martin has replicated these shims and sells them in the Big Jimny Shop here

If you have come from SJ ownership, or have worked on an SJ, note that the shims go on the pin itself and not around it on the top. On the SJ you add shims to relieve pressure on the bearings, on the Jimny you add them to add pressure to the bearings. So be careful not to do it wrong!


Adding kingpin shims ("shimming the kinpgins") is a tedious and time consuming process, as you have to do it incrementally - add a shim and test drive. If still not good, add more shims and test drive again, etc.

Alternative solution, which is much faster and much more expensive, is to buy new kingpins from Suzuki. Each front wheel needs two of them.

There are a few aftermarket kingpins available, but it is strongly recommended to use OEM ones, because of tight tolerances required.


Shimming the kingpins would be the most logical thing to to in the following case: You have recently installed good quality kingpin bearings and all was fine for a while. Then the death wobble has developed and you suspect that the system "kingpins + kingpin bearings" is the cause. Instead of replacing almost new kingpin bearings, it would be more logical to shim the kingpins.


11. Swivel Seals

Often thought of by "Landrover" experts to be a key problem, these are less of an issue on Jimny's.

The steering knuckle swivel seal on a Landrover is key to keeping the oil in the joint, but as a Jimnys joint is "dry" they act more as a dust shield.

However, as this seal also incidentally serves as soft of a "damper" for the steering, it may be worth changing them if you are getting desperate.


12. Front Wheel Bearings

Several user's experience with front wheel bearings on Jimny’s is that they are quite long lasting, which is handy as they are not cheap.

However, a worn wheel bearing can be the cause of death wobble, and also the cause of vacuum leak in the wheel hub, causing the 4WD engagement to fail.


Wheel bearings can be bought on the Big Jimny Shop: [4]


There is a guide on how to change them on the main Big Jimny Website: [5]


However, in order to change a front wheel bearing, you absolutely need a special tool to undo the front wheel bearing nut.

You can buy the required tool from the Big Jimny Shop too: [6]


Other considerations

1. Tyre Pressures

The standard Jimny Front Tyre pressure should be 1.6 bar (23 psi) on the front axle and 1.8 bar (26 psi) on the rear axle (don't ask why).

This is difficult to comprenend to most mechanics who are used to pumping every tyre which they get their hands on to the ubiquitous 2.0 bar, even if you tell them what pressure they should pump them to. Two bars is too much and too stiff for Jimny, so it can cause death wobble.

You should regularly check tyre pressures with a reliable pressure gauge. Don't trust gauges in petrol stations! It's like trusting that a prostitute has no STD. Buy yourself a personal gauge of good quality and carry it in the vehicle. Uneven tyre pressures are also a disbalance in the suspension system.


2. Brake discs

If the "death wobble" occurs only when braking (or is predominantly pronounced when braking), then you most probably have warped brake discs.

That is a standard issue common to any vehicle. It is easily sortable either by replacing the brake discs or having the existing ones grinded to remove the warps.

If you decide on replacing the discs, using genuine ones is the best insurance against the reoccurence of the warp. Some aftermarket brake discs have higher tendency to warp.

Grinding the discs to remove warps makes sense only if there is sufficient wear life left in them, and it can be done in certain workshops.


3. Collision damage

If you bought your vehicle second hand, it might have suffered a heavy collision in the past, which has bent or warped the chassis or one of the suspension or driveline components.

Even if the damage has been apparently successfully repaired, that does not mean that everything is exactly as it had been before.

If the chassis or any of the suspension components' geometry is out of specifications, it can certainly cause death wobble because the system is out of balance.


A good wheel alignment specialist with good equipment can detect if the chassis is bent or if some of the suspension components are bent, or if has been improperly repaired.

Also, a good bodywork restorer specialist should be able to detect the same deficiencies.


Unfortunately, it is quite difficult to return a bent/warped chassis or suspension components back into perfect alignment.


4. Paranormal causes

If none of all the above solutions mange to solve your death wobble, your vehicle might truly be possessed.


  1. You haven't been offroading through a derelict graveyard, have you !?
  2. Have you found yourself changing transmission modes in the moment of midnight, while being in motion or with front wheels not being straight ?
  3. Have you listened to satanic music when driving over 100 km/h in 4WD mode (or 50 km/h in 4WD-L mode)?
  4. If you have a soft top Jimny, did you have sex on the back seats with the soft top open under a full moon?
  5. Did you run over a cat or hit a crow while in 4WD-L mode?
  6. Does the DOT code on your tyres contain "666" numerals?
  7. Did you stick some el-cheapo Chinese-made "4x4", "4WD", "best 4x4xFar", "fuddy muckers" etc. badges and amulets on the car?


The only suggested solution would be to perform a mechanical exorcism. You need to find a priest with good mechanical skills. What is even more important, he has to have very strong faith in his mechanical skills. He should also be skilled in performing in-depth OBD2 vehicle diagnostics (not needed for Death Wobble, but who knows where the possession has extended itself in the meantime).


The procedure would be the following:

  1. Drive the possessed vehicle in the worst mud hole which you can find, and get stuck there. Then dig yourself out of the mud and store the dug out mud in some barrels. Bring those with you - you will need the mud later.
  2. Place the car on a podium, surrounded by five different rims, obtained from five different dead Jimnys from car junkyards. The rims need to be evenly spaced apart.
  3. Dig five holes somewhere nearby, so that a 33" tyre can easily fit in each hole.
  4. Tie each of vehicle's wheels to ground anchors with a good kinetic rope (or snatch strap) with at least 8T minimum breaking strength. The anchors need to be taken preferably from a Jeep Wrangler's or Nissan Patrol's heavy duty recovery points. Do not use tow balls for ground anchors as they are known to brake off!
  5. Remove the gearstick, the steering wheel the clutch pedal and the gas pedal, so the f****r can't make a move.
  6. For additional safety, remove the small propeller shaft between the gearbox and the transfer box.
  7. Now bring in the faithful mechanic.
  8. Bleed entire brake fluid. Do not panic if it happens to be dark red in colour.
  9. Put a worn retreaded tyre on top of each of those six rims, spray the tyres with leaded petrol (or agricultural diesel for DDiS Jimnys) - the fuel should be consecrated by the faithful mechanic beforehand - and then set the tyres on fire while reciting 6th and 7th page from chapter 3A from Suzuki's supplementary service manual 99501-81A00.
  10. Spray the burning tyres with the bleeded brake fluid, while reciting 2nd and 3rd page from chapter 3B from the same book.
  11. If the car begins to violently shake and skyrocket the engine RPMs while doing so, have your mechanic consecrate about a glass of WD-40 fluid and pour that in engine's air intake. That should tame it for a while. If still not good enough, try with brake disc cleaning fluid.
  12. If raging fire begins to erupt from the exhaust, get a tennis ball, write "Wobble this out" on it and stuck it hard in the exhaust pipe.
  13. Now get a big scepter (or a big consecrated hammer as the last resort) and have your faithful mechanic bang on the front wheel hubs while reciting 3rd and 4th pages from chapter 3D from Suzuki's service manual 99500-81A10.
  14. If the car still remains shaking and making awful engine noises, continue banging on the front differential housing, wheel hub assemblies, front radius arm to chassis mounts, front tie rod to chassis mount, axle to radius arm mounts, brake discs etc. while reciting the contents of related chapters from correct Suzuki's service manual. You must first obtain a correct manual based on your vehicle's VIN (see another chapter on that topic on BigJimny Wiki).
  15. You must do this fast before the tires burn out or both of you pass out from the burning tyres' toxic fumes.
  16. If you manage to successfully complete the exorcism (the car silences completely) before the tyres burn out, quickly put each of those five burning tyres in a hole which you dug out earlier, and then bury the burning tyres with the mud which you got in the first step of this procedure.
  17. Change your current rims with those five different rims on which the retreaded tyres were burning.
  18. Assemble all removed parts.


The exorcism should now be complete, but there is a chance that the demon has "laid low" somewhere in the vehicle (possibly in the vacuum system for front wheel hubs).


To make sure that the exorcism is complete, you need to perform the following check:

  1. Have the mechanic drive the car for at least 10 kilometers on a public road while keeping the speed strictly in the death wobble range (60-80 km/h) and trying not to brake. There should be no death wobble while doing so.
  2. If the mechanic develops a death wobble of his own while driving the car in the previous step (due to the awareness that there is no brake fluid in the car), than he has a crisis of faith and the entire procedure is in jeopardy. You have to write him off and find another righteous mechanic, and repeat the entire procedure again.
  3. If the car and the mechanic experience no death wobble while driving in the previous step, return the car to the podium and fill in new brake fluid.


The exorcism is now complete. The vehicle is clean and free!

Suppliers and Summary

There are other suppliers of many of the mentioned parts – The BigJimny Shop has been primarily mentioned as Martin runs this forum for us all and it has to be paid for somehow, along with his time in keeping it running.


See also though, in no particular order:

They are all great to deal with.


Steering damper

One other thing to "solve" death wobble is by adding a Steering Damper - available from most of the aforementioned suppliers.

However, installing the steering damper only masks death wobble, it does not solve it. It's like putting expensive makeup on an ugly face.

Steering damper is generally a good addition to a Jimny, but installing it solely to "solve" death wobble is doing it for the wrong cause.


Parts of the information are taken from the original thread at BigJimny Forums


Page last edited on 14/12/2016 by user Bosanek