Difference between revisions of "Death Wobble"
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== Introduction == | == Introduction == | ||
− | + | {{Gen3|}}{{Gen4|}} | |
* "Death Wobble" is a phenomenon where the steering wheel shakes, usually at around 35-45 mph (60-80 km/h). | * "Death Wobble" is a phenomenon where the steering wheel shakes, usually at around 35-45 mph (60-80 km/h). | ||
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* With big aggressive mud terrain tyres, or retreaded (remoulded) tyres, a little steering wheel shake may have to be lived with. | * With big aggressive mud terrain tyres, or retreaded (remoulded) tyres, a little steering wheel shake may have to be lived with. | ||
+ | |||
+ | |||
+ | {{note|This problem is quite common on Jimnys 3. Due to very similar suspension design, it is expected (but not yet observed as of 2019) to be a common occurrence on Jimny 4 too. If it does occur on a Jimny 4, 95% of the content of this article applies directly to it as well.}} | ||
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== Theory behind the phenomenon of "death wobble" == | == Theory behind the phenomenon of "death wobble" == | ||
− | + | {{Gen3|}}{{Gen4|}} | |
"Death wobble" is a known "genetic trait" of all vehicles which have '''dependent''' front suspension (typically solid front axle - SFA). | "Death wobble" is a known "genetic trait" of all vehicles which have '''dependent''' front suspension (typically solid front axle - SFA). | ||
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− | * King pin bearings appear to be the most common cause, followed by warped road wheels | + | * King pin bearings appear to be the most common cause, followed by improperly balanced wheels and then by warped road wheels. |
+ | |||
+ | {{note|The wiki article [[King pin bearing change|'''"King pin bearing change"''']] contains simple instructions on how to quickly diagnose if king pin bearings are worn.}} | ||
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− | * | + | ==== Introduction ==== |
− | ** | + | |
− | *** | + | |
− | *** If | + | * The primary reason why balancing is done in the first place is that neither tyres nor wheels are perfectly balanced themselves, nor are they perfectly round. |
− | * | + | ** When an object is unbalanced, it means that it has unequal weight distribution inside it. |
− | * If the | + | ** Rotating unbalanced objects (when object's center of mass is out of alignment with its center of rotation) creates a typical moment of wobbling movement. |
− | * | + | |
+ | |||
+ | ==== Minimizing the amount of balancing ==== | ||
+ | |||
+ | |||
+ | * There usually is something that can easily be done to make the wheel+tyre combination least unbalanced on its own, so that minimal balancing of that combination is required. | ||
+ | ** The less and smaller/lighter balancing weights that are installed, the less is the chance of an individual weight falling off later on, among several other benefits. | ||
+ | * The idea is to mount the tyre onto the wheel so that their dis-balances mostly cancel each other, creating an only lightly unbalanced combo which can be easily balanced with only a a few small balancing weights. | ||
+ | |||
+ | |||
+ | * Most (but not all) tyre manufacturers provide some type of simple aid in a form of a printed yellow and/or red dot on the sidewall of the tyre. | ||
+ | ** The yellow dot indicates tyre's lightest point, while a red dot indicates tyre's widest point (where its radius is largest). | ||
+ | * Also, most wheel manufacturers drill the valve stem hole in the heaviest point on the wheel (to partially mitigate that extreme), and some wheel manufacturers also punch or drill a small indicator hole or even put an indicating sticker in wheel's narrowest point (where its radius is smallest). | ||
+ | * Therefore, you could have a tyre with either red or yellow dot or even both dots (or no dots ....), and you could have a wheel with only the valve stem hole or with a small indicator hole or sticker as well. | ||
+ | ** So, what to align with with? | ||
+ | |||
+ | |||
+ | Here are the rules of alignment: | ||
+ | # If no dots are present on the tyre, you're s**t outta luck ... | ||
+ | # If only a yellow dot is present on the tyre, align it with the valve stem hole on the wheel. | ||
+ | # If only a red dot is present on the tyre, then look if the wheel has a small drilled/punched hole or an indicator sticker. | ||
+ | #* If there is one, align the red dot with that hole or sticker. | ||
+ | #* If there is not one, align the red dot with the valve stem hole. | ||
+ | # If both a red and a yellow dot are present on a tyre, in general case the red dot takes precedence over a yellow dot. | ||
+ | #* In that case, apply the above rules for the red dot and ignore the yellow dot (unless a tyre fitter strongly suggests otherwise). | ||
+ | |||
+ | |||
+ | ==== Proper balancing process ==== | ||
− | * | + | * If your tyres and road wheels are not warped, then balance your wheels again (even if you had done recently), but this time in a ''well equipped'', ''well trained'' and ''well reputed'' tyre workshop. |
− | * If you have the | + | * First ensure that the tyre on a wheel to be balanced is pumped to the correct [[Tyre selection and usage - best practices#Specific tyre pressures for Jimnys|tyre pressure]]. |
+ | ** Wheel balancing can produce different results with different tyre pressures! | ||
+ | ** Tyre pressure check should be done with a known accurate tyre air pressure measurement instrument. | ||
+ | * Personally check with them if they have the fully & properly matching tool/seat for '''your''' wheels when they mount the wheel on their balancing machine. | ||
+ | ** Some poor / skimpy / unethical tyre workshops will improvise with improperly matching seats for wheels on their balancing machine just to get the job (apparently) done and take the customer's cash. | ||
+ | ** If an improper/mismatched wheel seat is used, the measurement on the balancing machine will be significantly inaccurate, defeating the purpose of the job. | ||
+ | ** If you have steel wheels, insist that they use the seat that uses the wheel bolt holes ("stud centric balancing") to secure the wheel to the balancing machine instead of using the more common (and quicker for them to get the job done) cone seat through the center of the wheel ("hub centric balancing"). | ||
+ | *** The "hub centric" balancing has a risk of giving different results on different testing iterations - you want to avoid that risk. | ||
+ | * Also don't forget to try to apply the tyre/wheel mounting alignment principles (mentioned in other parts of this chapter) to minimize the amount of needed balancing in the first place. | ||
+ | ** Many tyre fitter's don't care to care about this mounting alignment! | ||
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Example of such a machine is "Hunter RoadForce" wheel balancer. | Example of such a machine is "Hunter RoadForce" wheel balancer. | ||
+ | |||
+ | |||
+ | ==== After the balancing with balancing weights ==== | ||
+ | |||
+ | |||
+ | * After the balancing with balancing weights 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, saving yourself immense amounts of time, money and nerves. | ||
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Beads are sort of "alternative medicine" compared to conventional balancing weights, but if it cures, then it's good! | Beads are sort of "alternative medicine" compared to conventional balancing weights, but if it cures, then it's good! | ||
+ | |||
+ | |||
+ | ==== Other notes ==== | ||
+ | |||
+ | |||
+ | * 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. | ||
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{{spanner|Guide: [[Tie rod end replacement|'''"How to replace tie rod ends"''']]}} | {{spanner|Guide: [[Tie rod end replacement|'''"How to replace tie rod ends"''']]}} | ||
− | |||
* You can buy new ones from the BigJimny Shop, which sells both (OEM) ones and aftermarket made ones. | * You can buy new ones from the BigJimny Shop, which sells both (OEM) ones and aftermarket made ones. | ||
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* 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. | * 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 rubber bushes. | * However, if you are battling death wobble and are tired of experimenting, then buy the OEM rubber bushes. | ||
+ | |||
+ | |||
+ | The following forum threads deal with the topic of polyurethane bushes: | ||
+ | # [http://www.bigjimny.com/index.php/forum/7-jimny-technical/65092-poly-bushes-for-panhard-rods-are-they-worth-it?start=0 "Poly bushes for panhard rods - are they worth it"] | ||
+ | #* Both panhard rod and radius arm bushes are discussed in this topic. | ||
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* Unfortunately, Suzuki does not sell lateral rod bushes separately. They sell only the entire lateral rod with the bushes already installed. | * Unfortunately, Suzuki does not sell lateral rod bushes separately. They sell only the entire lateral rod with the bushes already installed. | ||
− | * The only known aftermarket manufacturer which sells ''rubber'' lateral rod bushes for Jimny is Febest. | + | * The only known aftermarket manufacturer which sells ''rubber'' lateral rod bushes for Jimny 3 is [http://www.febest.com Febest]. |
+ | ** Compatible part number is [https://febest.de/en/details/rear_transverse_rod_bushing-szab_041 SZAB-041]. | ||
* You can buy replacement ''polyurethane'' lateral rod bushes from the Big Jimny Shop : [http://bigjimny.com/store/index.php?_a=product&product_id=28] | * You can buy replacement ''polyurethane'' lateral rod bushes from the Big Jimny Shop : [http://bigjimny.com/store/index.php?_a=product&product_id=28] | ||
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* Front wheels rotate left-right on king pin bearings. | * Front wheels rotate left-right on king pin bearings. | ||
− | * Jimny uses four king pin bearings | + | * Jimny uses four king pin bearings - two per each front wheel. |
* King pin bearings are the main reported cause of death wobble on this forum. | * King pin bearings are the main reported cause of death wobble on this forum. | ||
* The longevity of Jimny's king pin bearings is typically rather short, because of relatively easy ingress of water and mud into the steering knuckles (poor design). | * The longevity of Jimny's king pin bearings is typically rather short, because of relatively easy ingress of water and mud into the steering knuckles (poor design). | ||
− | + | {{note|The wiki article [[King pin bearing change|'''"King pin bearing change"''']] contains simple instructions on how to quickly diagnose if king pin bearings are worn.}} | |
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
− | |||
{{spanner|Guide: [[King pin bearing change|'''"How to replace king pin bearings"''']]}} | {{spanner|Guide: [[King pin bearing change|'''"How to replace king pin bearings"''']]}} | ||
− | + | * The bearing manufacturer for Suzuki is KOYO. | |
− | * The bearing manufacturer for Suzuki | + | * If you buy your king pin bearings from the [http://bigjimny.com/store/index.php?_a=product&product_id=6 Bigjimny Shop], you will at the time of writing get KOYO’s, so you know they are the correct spec. |
− | * If you buy your king pin bearings from the | ||
* Another good king pin bearings are from manufacturer SKF - bearing model "30302 J2". | * Another good king pin bearings are from manufacturer SKF - bearing model "30302 J2". | ||
+ | * A half axle oil seal comes together with the king pin bearings when bought from the Big Jimny Shop – replace it while everything is dismantled anyway. | ||
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{{spanner|Guide: [[Front wheel bearing replacement|'''"How to replace a front wheel bearing"''']]}} | {{spanner|Guide: [[Front wheel bearing replacement|'''"How to replace a front wheel bearing"''']]}} | ||
− | |||
* However, in order to replace a front wheel bearing, you absolutely need a special tool to undo the front wheel bearing nut. | * However, in order to replace a front wheel bearing, you absolutely need a special tool to undo the front wheel bearing nut. | ||
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{{Edited}} | {{Edited}} | ||
+ | |||
+ | [[Category:Common_Problems - gen2]] | ||
+ | [[Category:FAQ - gen2]] | ||
[[Category:Common_Problems - gen3]] | [[Category:Common_Problems - gen3]] |
Latest revision as of 12:17, 5 December 2021
The content of any article might be expanded / improved in the future - revisit it sometimes.
Seen a mistake? Know something that isn't written? Edit and change this article yourself!
Some images in the article (if present) can be enlarged by clicking on them.
Contents
- 1 Introduction
- 2 Theory behind the phenomenon of "death wobble"
- 3 General procedure of solving death wobble
- 4 Detailed remarks about each step in solving death wobble
- 4.1 Brake discs
- 4.2 Tyre pressures
- 4.3 Collision damage
- 4.4 Cleanliness
- 4.5 Warped (distorted) tyres
- 4.6 Warped (distorted) road wheels
- 4.7 Wheel balancing
- 4.8 Track Rod Ends / Steering Rod Ends
- 4.9 Adjusting the steering box
- 4.10 Wheel alignment
- 4.11 Radius Arm / Trailing Arm Bushes
- 4.12 Lateral (Panhard) Rod Bushes
- 4.13 King Pin Bearings
- 4.14 Shimming or replacing King Pins
- 4.15 Swivel Seals
- 4.16 Front Wheel Bearings
- 4.17 Steering damper
- 5 Paranormal causes
- 6 Suppliers and Summary
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.
This problem is quite common on Jimnys 3. Due to very similar suspension design, it is expected (but not yet observed as of 2019) to be a common occurrence on Jimny 4 too. If it does occur on a Jimny 4, 95% of the content of this article applies directly to it as well.
The Videos
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:
The third video shows the case of a truly extreme death wobble in a Jimny (skip the playback to 0m20s):
Theory behind the phenomenon of "death wobble"
"Death wobble" is a known "genetic trait" of all vehicles which have dependent front suspension (typically solid front axle - SFA).
The elements which make a suspension system are all the various rods, arms, joints, springs, bushes, bearings and mounts, as well as the road wheels and tyres themselves. The wheels and tyres are often the overlooked elements.
- Dependent suspension means that the left and right side of the axle are connected.
- 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 roughly 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 suspension 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
Introduction
- The disbalance or play can even be caused by trivial causes such as dirt (like mud deposits on road wheels), or rusty contact surfaces between the road wheel and the wheel hub for example.
- It is also possible that a balancing weight on a road wheel has fallen off in the meantime, so the wheel has lost its balance.
The point is:
- The problem needs systematic approach to solve, as it can be be very expensive and time consuming to replace parts on random guessing.
First considerations
- Before tampering with anything, observe if the death wobble occurs only (or predominantly) when braking. If it does, then the most probable cause is warped brake discs. That isn't the classic death wobble that we are dealing with here. See the subchapter "Brake discs".
- Frequently check your tyre pressures with a reliable air pressure measurement instrument. Tyre pressure discrepancy can cause death wobble. See the subchapter "Tyre pressures".
- Are you certain that the vehicle has had no collision damage in the past? The chassis or suspension components might have been bent from the impact, and even if repaired, it might have not been perfectly done. If some of this is true, you should attend that problem first, because no matter which common parts you replace, it might be in vain if the vehicle's structure itself is bad or "FUBAR".
If you are good on these three checks, then congratulations - you have a standard death wobble. Read the following subchapters to get the overview of the systematic approach to resolving it.
The summary of the approach
- Check if anything is obviously or measurably worn or warped, and remedy that first.
- If death wobble still persists, replace parts preventively in the order from the simplest, cheapest or most common fixes or replacements first, and advance toward more expensive or complicated ones if necessary.
- If the issue still is not solved, refer to Paranormal issues and solutions.
Checking for warped or worn parts
- Check if a wheel balance weight is missing (prerequisite is a prior inventory of attached wheel balance weights).
- Clean the road wheels and wheel hubs where they meet each other, and also clean the mating surfaces of disc brakes and wheel hubs.
- Check if the tyres are warped.
- Check if the road wheels are warped.
- Balance the road wheels in a well equipped workshop.
- Check for worn king pin bearings.
- Check for worn tie rod ends.
- Check for worn front wheel bearings.
- Check for worn radius arm bushes.
- Check for worn lateral (panhard) rod bushes.
- Check for excessive play in the steering box (read notes further below!).
- Perform professional wheel alignment in a well equipped workshop (wheel alignment has to be performed anyway after any tie rod end replacement).
- Check for worn steering knuckle swivel seals.
If any of the parts from the list show obvious signs of wear, than repair or replace without hesitation.
- King pin bearings appear to be the most common cause, followed by improperly balanced wheels and then by warped road wheels.
The wiki article "King pin bearing change" contains simple instructions on how to quickly diagnose if king pin bearings are worn.
- Always use only genuine OEM spare parts or proven aftermarket replacements (for example, Suzuki uses Koyo bearings).
- Such parts have the best quality and therefore the smallest manufacturing tolerances, minimizing the chance that the new part will not solve or even worsen your problem.
- If your tyres are quite worn or more than 5-6 years old, it might be just the right time (and the right excuse) to buy new tyres - a chance to treat yourself with something new.
- That might even solve the death wobble, because old and worn tyres can become naturally warped and stiff.
- Read the wiki article "Tyre selection and usage - best practices" for guidelines.
If you manage to solve your death wobble in this phase of the process, consider yourself lucky.
- Beware that some parts might be worn without showing obvious signs when testing them (examples are king pin bearings and wheel bearings).
- So, if you are that unlucky, you will have to advance to the next step.
Preventively replacing parts
If you fail to find anything obviously worn, or the death wobble persists after you replace detected worn parts, then you have to start changing items preventively until you hopefully hit a lucky strike.
Here is the list of what you should do in the listed order, as it has generally been ordered from the the simplest, cheapest or most common fixes or replacements first, towards more expensive or complicated ones at the bottom of the list.
- You might try using balance beads instead of balance weights for balancing the tyres.
- Replace king pin bearings (the bearings on which the front wheels turn left-right).
- Replace front radius arm bushes which connect them with the chassis, especially if your Jimny was made before 2008 and still has factory-installed bushes.
- Replace front wheel bearings.
- Replace king pins or insert custom shims under the king pins.
- Replace tie rod ends.
- Perform professional wheel alignment in a well equipped workshop (wheel alignment has to be performed anyway after any tie rod end replacement).
Hopefully you will solve your death wobble before you reach the end of this list.
Last resort
If you got to this section, it means you are desperate.
But there is one more thing which could be the cause. See Paranormal issues and solutions.
Detailed remarks about each step in solving death wobble
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.
Tyre pressures
- The standard (on-road) Jimny tyre pressures (with factory-size tyres) 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 it's higher on the lighter rear axle ...)
- These low pressures are 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.
- 2 bar is too much and too stiff for Jimny, so it can cause death wobble.
- Also, uneven tyre pressures on the same axle are bad in many ways, and can also trigger death wobble because they disbalance the suspension system.
- Therefore, you should regularly check your 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.
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.
- You can also do some checking yourself - check/measure the underbody (chassis, suspension, driveline) thoroughly for any bents, and also for asymmetries between the left and the right side.
- For example, measure the distance (clearance) between the left coil spring and left chassis rail, and compare that with the distance between the right coil spring and right chassis rail.
- Any detected asymmetry should be further investigated by a professional.
- Note: The front lateral (panhard) rod on LHD Jimnys is bent by design (to accommodate the front differential casing).
Unfortunately, it is quite difficult to return a bent/warped chassis or suspension components back into perfect alignment.
Cleanliness
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!?
- So, each time when you rotate or change the wheels, preventively check if the road wheels and wheel hubs are clean, especially where they meet each other.
- If not, clean them.
- If you have the death wobble, also clean the mating surfaces of disc brakes and wheel hubs.
- This cleanliness extends to the sealant used in rebuilding the wheel hub.
- Do not use too much on the king pins themselves as this creates a layer when prevents the king pin from seating correctly.
- Also ensure that the king pin itself is rust free.
- Also, it has been confirmed several times that "temporary" death wobble develops whenever road wheels get filled with mud or snow.
- As soon as you wash them good (or the snow melts away), the death wobble is gone.
So be tidy!
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 tyre construction 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 chunky tyres, you are dancing with the devil on his podium.
Warped (distorted) road wheels
- Death wobble can be caused by bent (wobbly) road wheels, either steel or alloy.
- This was the sole cause of death wobble for BigJimny forum user Bosanek.
- In many cases the road wheel 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 road wheels.
- Bosanek solved his death wobble by having his alloy road wheels repaired in this manner.
- Therefore, whenever you go to balance your wheels, you should go to a well equipped, well trained and reputable tyre workshop, and ask them to check your road wheels for distortions as well, and repair them if found.
- It is best to repair warped wheels at the same time when changing or buying new tyres.
An example of a specialist road wheel repair workshop in United Kingdom is Rimmaster.co.uk. (link is provided just as an example, nothing is known about their quality of work)
Wheel balancing
Introduction
- The primary reason why balancing is done in the first place is that neither tyres nor wheels are perfectly balanced themselves, nor are they perfectly round.
- When an object is unbalanced, it means that it has unequal weight distribution inside it.
- Rotating unbalanced objects (when object's center of mass is out of alignment with its center of rotation) creates a typical moment of wobbling movement.
Minimizing the amount of balancing
- There usually is something that can easily be done to make the wheel+tyre combination least unbalanced on its own, so that minimal balancing of that combination is required.
- The less and smaller/lighter balancing weights that are installed, the less is the chance of an individual weight falling off later on, among several other benefits.
- The idea is to mount the tyre onto the wheel so that their dis-balances mostly cancel each other, creating an only lightly unbalanced combo which can be easily balanced with only a a few small balancing weights.
- Most (but not all) tyre manufacturers provide some type of simple aid in a form of a printed yellow and/or red dot on the sidewall of the tyre.
- The yellow dot indicates tyre's lightest point, while a red dot indicates tyre's widest point (where its radius is largest).
- Also, most wheel manufacturers drill the valve stem hole in the heaviest point on the wheel (to partially mitigate that extreme), and some wheel manufacturers also punch or drill a small indicator hole or even put an indicating sticker in wheel's narrowest point (where its radius is smallest).
- Therefore, you could have a tyre with either red or yellow dot or even both dots (or no dots ....), and you could have a wheel with only the valve stem hole or with a small indicator hole or sticker as well.
- So, what to align with with?
Here are the rules of alignment:
- If no dots are present on the tyre, you're s**t outta luck ...
- If only a yellow dot is present on the tyre, align it with the valve stem hole on the wheel.
- If only a red dot is present on the tyre, then look if the wheel has a small drilled/punched hole or an indicator sticker.
- If there is one, align the red dot with that hole or sticker.
- If there is not one, align the red dot with the valve stem hole.
- If both a red and a yellow dot are present on a tyre, in general case the red dot takes precedence over a yellow dot.
- In that case, apply the above rules for the red dot and ignore the yellow dot (unless a tyre fitter strongly suggests otherwise).
Proper balancing process
- If your tyres and road wheels are not warped, then balance your wheels again (even if you had done recently), but this time in a well equipped, well trained and well reputed tyre workshop.
- First ensure that the tyre on a wheel to be balanced is pumped to the correct tyre pressure.
- Wheel balancing can produce different results with different tyre pressures!
- Tyre pressure check should be done with a known accurate tyre air pressure measurement instrument.
- Personally check with them if they have the fully & properly matching tool/seat for your wheels when they mount the wheel on their balancing machine.
- Some poor / skimpy / unethical tyre workshops will improvise with improperly matching seats for wheels on their balancing machine just to get the job (apparently) done and take the customer's cash.
- If an improper/mismatched wheel seat is used, the measurement on the balancing machine will be significantly inaccurate, defeating the purpose of the job.
- If you have steel wheels, insist that they use the seat that uses the wheel bolt holes ("stud centric balancing") to secure the wheel to the balancing machine instead of using the more common (and quicker for them to get the job done) cone seat through the center of the wheel ("hub centric balancing").
- The "hub centric" balancing has a risk of giving different results on different testing iterations - you want to avoid that risk.
- Also don't forget to try to apply the tyre/wheel mounting alignment principles (mentioned in other parts of this chapter) to minimize the amount of needed balancing in the first place.
- Many tyre fitter's don't care to care about this mounting alignment!
"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.
- 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.
Example of such a machine is "Hunter RoadForce" wheel balancer.
After the balancing with balancing weights
- After the balancing with balancing weights 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, saving yourself immense amounts of time, money and nerves.
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 road wheel) and they dynamically balance the entire wheel + tyre assembly 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!
Other notes
- 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.
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.
- You can buy new ones from the BigJimny Shop, which sells both (OEM) ones and aftermarket made ones.
- You need one standard threaded "end" and one reverse threaded "end" per rod – so 2 of each for the whole car.
It is necessary to perform professional wheel alignment (https://en.wikipedia.org/wiki/Wheel_alignment) after any tie rod end replacement.
- Considering that obligatory alignment work and expense after each tie rod end replacement, 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.
Adjusting the steering box
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 user and service manuals.
- The officially stated range of "normal" amount of play in the steering wheel is 0 - 30 mm.
- This is quite a wide range of officially acceptable play, but it has to be respected, as the steering box is designed for it.
- Adjusting the steering box should be used with extreme caution!
- If you overtighten it or overslack it too much, it can wear prematurely.
- The steering box is giga-mega-uber-super-duper-ridiculously expensive.
Wheel alignment
- As already said, it is necessary to perform professional alignment after any tie rod end replacement.
- However, doing wheel alignment just on itself might be a good idea to cheaply and quickly resolve death wobble (and solve some other issues along the way).
- The alignment can get out of order if you hit hard a big bump, hole or sidewalk, or if you drive hard off road.
- Wheel misalignment could cause suspension disabalance.
- It is important to do the wheel alignment in a reputable workshop with advanced equipment and trained personnel.
- Don't go to someone who still uses ropes or rulers to perform wheel alignment, no matter how old and experienced they are and in how many wars they had fought.
- Much more accurate and functional laser-guided, computerized wheel alignment machines have been invented well before 21st century came about.
- Don't go to someone who still uses ropes or rulers to perform wheel alignment, no matter how old and experienced they are and in how many wars they had fought.
- For example, Hunter makes advanced and proven wheel alignment machines.
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 radius arms.
- 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.
- Those revised 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 both 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 strictly the revised ones for the position of the connection with the chassis.
Note about polyurethane bushes
- Polyurethane bushes are an alternative which is slightly more expensive in some cases, but easier to fit and typically much more durable.
- The best come from Super Pro and can be bought from a number of places – Off Road Armoury, Bits4Vits, Jimnybits, KAP Suzuki, etc.
- 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 rubber bushes.
The following forum threads deal with the topic of polyurethane bushes:
- "Poly bushes for panhard rods - are they worth it"
- Both panhard rod and radius arm bushes are discussed in this topic.
Lateral (Panhard) Rod Bushes
- Lateral (panhard) rod bushes are there to restrict lateral axle movement.
- Therefore, any extra movement can translate to death wobble.
- Unfortunately, Suzuki does not sell lateral rod bushes separately. They sell only the entire lateral rod with the bushes already installed.
- The only known aftermarket manufacturer which sells rubber lateral rod bushes for Jimny 3 is Febest.
- Compatible part number is SZAB-041.
- You can buy replacement polyurethane lateral rod bushes from the Big Jimny Shop : [1]
- Beware that the panhard rod bush mounting holes can wear to an "oval" shape, allowing the rod to move.
King Pin Bearings
- Front wheels rotate left-right on king pin bearings.
- Jimny uses four king pin bearings - two per each front wheel.
- King pin bearings are the main reported cause of death wobble on this forum.
- The longevity of Jimny's king pin bearings is typically rather short, because of relatively easy ingress of water and mud into the steering knuckles (poor design).
The wiki article "King pin bearing change" contains simple instructions on how to quickly diagnose if king pin bearings are worn.
- The bearing manufacturer for Suzuki 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.
- Another good king pin bearings are from manufacturer SKF - bearing model "30302 J2".
- A half axle oil seal comes together with the king pin bearings when bought from the Big Jimny Shop – replace it while everything is dismantled anyway.
Shimming or replacing King Pins
- Each king pin bearing is tightly connected with a king pin.
- King pin's purpose is to securely hold the wheel knuckle assembly to the axle swivel, while allowing it to freely rotate on the pair of king pin bearings.
- It's a "tightly tuned" system.
- If the king pin is worn, rusty, not seated properly or provides insufficient or excessive load on the king pin bearing during operation, that can either cause vibrations, or premature wear of the king pin or (more likely) the king pin bearing, which will again cause vibrations after a while.
- The pre-load on the king pin 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 the 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 (Samurai) 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 king pin shims ("shimming the king pins") 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, is to buy new king pins from Suzuki.
- Each front wheel needs two of them.
- New king pins are quite expensive, but if the labour cost is high, it might pay off to buy them new to (hopefully) resolve the issue in one strike.
- There are a few aftermarket king pins available, but it is strongly recommended to use OEM ones, because of tight tolerances required.
Shimming the king pins would be the most logical thing to to in the following case:
- You have recently installed good quality king pin bearings and all was fine for a short while.
- Then the death wobble has developed and you suspect that the system "king pins + king pin bearings" is the cause.
- Instead of replacing almost new king pin bearings, it would be more logical to shim the king pins.
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 Land Rover is key to keeping the oil in the joint, but as Jimny's joint is "dry" they act more as a dust shield.
- However, as this seal also incidentally serves as sort of a minor "damper" for the steering, it may be worth changing them if you are getting desperate.
Front Wheel Bearings
- Several users' experience with front wheel bearings on Jimnys is that they are quite long lasting, which is handy as they are not cheap and it is not cheap nor simple to replace them.
- However, a worn wheel bearing can be the cause of death wobble, and also the cause of a vacuum leak in the wheel hub, causing the 4WD engagement to fail.
- In some circumstances a worn wheel bearing does not give detectable signs.
- Wheel bearings can be bought on the Big Jimny Shop: [2]
- However, in order to replace 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: [3]
Steering damper
- A typical "first choice" to "solve" death wobble is to add a steering damper - available from most of the aforementioned suppliers.
- However, installing the steering damper can only mask the death wobble (if you are lucky), it does not solve it.
- It's like putting elaborate makeup on an ugly face.
- In many cases, a steering damper can not even mask the death wobble, because the frequency of the death wobble vibrations typically exceeds the dynamic damping capacity of the steering damper.
- Steering damper is generally a good addition to a Jimny, but installing it primarily to "solve" death wobble is doing it for the wrong cause.
- See more in the wiki article "Steering damper".
Paranormal causes
If none of all the above solutions manage to solve your death wobble, your vehicle might truly be possessed.
- You haven't been offroading through a derelict graveyard, have you !?
- Have you found yourself changing transmission modes in the moment of midnight, while being in motion or with front wheels not being straight ?
- Have you listened to satanic music when driving over 100 km/h in 4WD mode (or 50 km/h in 4WD-L mode)?
- If you have a soft top Jimny, did you have sex on the back seats with the soft top open under a full moon?
- Did you run over a cat or hit a crow while in 4WD-L mode?
- Does the DOT code on your tyres contain "666" numerals?
- 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 mechanical exorcism procedure
- Drive the possessed vehicle in the ugliest mud hole which you can find, and get stuck there. Then dig yourself out of the mud manually with a shovel, and store the dug out mud in some barrels. Bring those barrels with you - you will need the mud later.
- Place the car on a podium, surrounded by five different road wheels, obtained from five different dead Jimnys from vehicle junkyards. The wheels need to be evenly spaced apart around the vehicle.
- Dig five holes somewhere nearby, so that a 33" tyre can easily fit in each hole.
- 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 ground 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!
- Remove the gearstick, the steering wheel, the clutch pedal and the gas pedal, so the f****r can't make a move.
- For additional safety, remove the small propeller shaft between the gearbox and the transfer box.
- Now bring in the faithful mechanic.
- Bleed entire brake fluid. If you suddenly realize that it's blood, do not panic. There's worse to come.
- Get five worn retreaded tyres from any all-terrain vehicle, and put each tyre on top of each of those five road wheels. Then 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.
- Sprinkle the burning tyres with the bleeded brake fluid, while reciting 2nd and 3rd page from chapter 3B from the same book.
- If the car begins to violently shake and skyrocket the engine RPMs while you are spraying the burning tyres, 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.
- 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. Write that in Cyrillic scripture for Japanese-made Jimnys (VIN beginning with "JSA...."), or in Arabic scripture for Spanish-made Jimnys (VIN beginning with "VSE....").
- 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.
- Proceed to bang on the front differential housing, road wheels, 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).
- If the car keeps on shaking and making awful engine noises while you are banging it, that is just an additional confirmation that you are barking at the right tree.
- You must do all this banging fast before the tyres burn out or both of you pass out from the burning tyres' toxic fumes.
- After you bang all those elements out with proper chanting, and before the tyres burn out, quickly put each of those five burning tyres in five holes which you had dug out earlier, and then bury the burning tyres with the mud which you got in the first step of this procedure.
- Replace your current road wheels with those five different wheels on which the retreaded tyres were burning.
- Assemble all removed parts. Don't forget to remove the tennis ball if it's still there. Bury it too.
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:
- 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.
- 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 has been jeopardized. You have to write him off and find another righteous mechanic, and repeat the entire procedure again.
- 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.
Parts of the information are taken from the original thread at BigJimny Forums
Page last edited on 5/12/2021 by user Bosanek