5th Gen Steering Wheel Shake: SOLUTIONS ONLY

Has anyone tried cranking in a little more caster?

 

Reading everybody's descriptions, I would agree. I suspect the shimmy is a harmonic/resonance is occurring.

Disclaimer: Im not an engineer, but I watched a show on engineering once . But, if the shimmy is a resonance/ harmonic situation, I think these questions need to be answered.

1. If the wheels are well balanced, what is inducing the harmonic?

One theory is the whole “loud needle bearing problem”. In my mind, I’ve always pictured the loud needle bearing as a harmonic noise caused by the poor tolerances at the DS front diff, so this theory appeals to me.

In analogy form, this would be the striker that hits the tuning fork, or the opera singer’s voice that break the glass.

2. Once the harmonic is induced, what is transmitting or carrying it? It other words, what parts are involved in carrying the musical note? Is it just the, wobble of suspension and/or control arms within their bushings? The actual frame???




I think if we can answer either what induces the harmonic, and what transmits it, we’ll have a resolution to the steering shimmy.

Still hoping somebody throws it into 4wd and makes a shimmy stop dead in it’s track! That would be an easy way to find out if the needle bearing is inducing the chain if events.

 

Out of ignorance, I have thrown it in to 4WD at highway speed - probably above 60 MPH. While the owners manual says not to do that above 50 MPH, it would be interesting to know if doing so immediately stops the shimmy.

I don't have the shimmy - unless I let my truck sit for a week. Then sometimes I get a little for the first couple of miles on the highway, then smooth. I have attributed this to temporary flat spots on the tires from sitting too long.

 

Is this an overlooked possibility? Everyone drives different amounts. Is this affecting daily driven 4runners?

 

The last three weeks I have driven my Runner daily as my Tacoma was in the shop (I upgraded my 2015 Tacoma AC TRD Sport 2WD front rotors and calipers to 4Runner rotors and calipers). I have not had shimmy during that time - I run 275/65R18 Nitto Ridge Grapplers. My suspension is upgraded to Toytec Coilovers with Bilstein 6112s up front.

 

Yes. My shimmy appeared after switching to TRD wheels and new tires. It continued after increasing the caster. I do not know what my caster specs at, but it must be around the max of the recommended range because the wheels are pushed forward enough that I get a slight rubbing of the tire tread on the fender liner when turning in reverse. The higher caster has been a boon for tracking on the highway -- really glad I did it, it's almost transformative. But it certainly neither caused nor cured my shimmy.

The needle bearing theory is intriguing, but... I have a Limited so it is always in 4WD and I understood that the needle bearing doesn't exist in this setup, or is not a problem in this design, as issues with the bearing seem to have been reported only by the owners of part-time 4WD rigs. Regardless, it would be interesting to hear from guys who ditched their needle bearings. Have any of them had the shimmy since doing that?

As is well documented on the forum, the shimmy problem exists in every model within the 4R lineup, regardless of suspension, 4WD system or presence or lack of mods.

While not an engineer, I certainly do think there's some kind of harmonics at play. It's a "sympathetic vibration" set off by a combination of common but unknown factors, and results from a design weakness that is common to all 4Runners. My guess is it's in the steering rack or column, or perhaps in the front frame / suspension mounts.

 

I don’t have the vibes on the 4Runner, but I haven’t lifted it yet. I did on my 2.5 Gen Tacoma. I gave it a lot of TLC & so far so good. The top 3 upgrades were SPCs, new tires & reconstructed calipers.

New OEM LCAs & eccentrics
New tires - 265/70/17 falkens
New rims - 4Runner TRD rims
Toytec 2” lift kit - Bilstein/eibach/boss
New oem rotors, pads & reconstructed calipers with SPC UCAs
ecgs bushing, carrier & diff drop
Toytec sway bar drop

No more nose dive & no vibes now!

 

I believe you are correct that limiteds dont have the needle bearing problem. That’s a strike against the needle bearing theory.

If shimmy exists on 2wd runners with the same frequency, that would finish the needle bearing theory….

Have people experimented with more toe-in (not just caster)?

 

I'm still convinced it's a wheel balance issue.

There's multiple people who report NO vibes before a tire rotation and then vibes after said rotation.

The balance needs to be almost prefect for there to be no vibes and do you think tire shops are getting things close to perfect on everyone's rigs? Not to mention the tires need to be perfect as well. Seems like a lot of people are switching tires that are found to be bad after trying to road force balanced. How many of those bad tires have not been found to be bad yet?

Lastly, wheels fall out of balance all the time. You'd probably have to go once every couple months to stay on top of a perfect balance, but who has time for that?

 

I think this is probably right. The question remains however — why is the 4Runner so sensitive to even a minor imbalance? That’s the issue.

Most vehicles would shrug it off. Ours are instead hyper sensitive. The fact that no one has come up with a cure for that hyper sensitivity tells me it’s an unsolvable problem. It’s probably a quirk of rack or suspension mounting points or some other part of the frame.

 

On every vehicle I have ever owned I never needed more than one balance, even with ko2’s for 3 years 50,000 miles +

 

I did this 2 nights ago on my way home from work, I swore it make it less intense as it was bad that drive, but didn’t fully take it away. Went in and out of 4 wheel drive 3 times making sure I wasn’t going crazy as I did work a 17 hour shift.

 

Has anyone tried balance beads?

 

You know, I’d normally think this would just be covering up a symptom. But, if the 4runner is honestly that sensitive to balance, maybe dynabeads really are the right way to go.

At least it’s worth a shot.

 

WHO IS GONNA BE THE TESTER!?!?!?

 

I only had the shimmy happen once ever, last week (knock wood). Im afraid I wouldn't be a good source to get enough data to solve this problem…

If only there was someone that experiences this more regularly…and with varying amounts severity…hmmm


Oh look! A link!!!

Whoever takes up this burden will no doubt become legend…children will be told stories of his deeds, and his story may even be enshrined as a sticky threads.

 

Check other 4R forums for 4Runner owners’ experience with balance beads. It’s not new.

I’ve seen mixed results reported. Most users still recommended getting a good road force balance.

 

Balance beads won't work if you don't use enough. I'd bet that most people that had a bad experience with dyna beads bought 4oz when they needed 10. Dyna beads customer service will help you determine what you need.
Road force balance is only as good as the tech doing the job. Alot of tire monkeys don't know or care to do a good balance.

 

Can you confirm the beads fixed the shakes?

 

Ignore it. It will go away once your tires heat up.

Been driving my Jeep a lot lately. Took my 4Runner out yesterday and had a whole bunch of tire shimmy. Adjusting my speed and letting the tires heat up, it quickly went away.

 

Fascinating because I did ignore it when my wheel started to shake at highway speed and it continued for 58 minutes on the highway so perhaps my tires needed even more warming? I highly doubt tire temps are the fix all for this issue. As noted 2 days later on my return trip I had no shimmy as experienced on the drive up.

 

No, they don't work.

They don't help with low speed balance issues.
They don't help with shakes not related to balance.
They won't fix anything if you don't install the proper amount.

 

Hopes are being dashed left and right…. Has anyone tried grabbing the steering rack to see if it’s loose?

 

Works been kicking my ass lately so its been a slow burn around getting my lift put on. Plan is: get the lift wrapped up, diff drop kit, sway-bar extensions, complete fluid swap front to back (4R is nearing 120k miles) and once thats ALL done I'll be running through a crap ton of tests to see what the shimmy is like post lift install, and how bad its gotten with the added angle on the CVs. I'll report back how that looks, and depending on those tests I'm probably going to swap the bearing over to the Yukon Gear and Axle or ECGS part. I'll report after the swap what the improvement has been if any at all in relation to the shimmy.

I will say I do have a bit of play on the my driver side CV, at the IFS not the wheel itself. I've checked LITERALLY everything else. I've been tracking this issue down since my first set of K02s ~6 years ago. I am on my 3rd set now..... I've gone through the entirety of the front suspension and steering with a fine toothed comb. The ONLY issues I spotted, were the excessive play on the CV, AND somewhat worn out tie-rod ends (which aren't really even that worn out, just looking a little tired). Past that everything else checked out. Rotors and brakes have been changed twice all around, so its definitely not a warped rotor either. Idk... I feel like I've ran this entire thing down from every angle for quite some time to no avail. The closest I feel I've gotten is the needle bearing but that could just be me trying to force myself into a solution to be done with all this crap haha.

That said, I really have a very hard time believing this truck is THAT sensitive to balance and harmonics. Our IFS set up as well as our powertrain AND the general frame that underpins our 4R platform has been around a VERY VERY long time. If the IFS was THAT susceptible to balance and harmonics I'd feel like this would be a bigger topic in the community. Would love to hear if anyone's been able to get this shimmy to disappear with a different set of tires that are non-A/T, I wonder if anyone with a 2wd platform feels the shimmy at all, those of you that have done the TSB for this very shimmy with swapping the front-diff out at the dealership, has your shimmy come back? Did they list what parts they changed over? Curious if the needle bearing and axle seal are on the parts list for that TSB.

There's WAY too many variables to confidently narrow down on a culprit, or to be able to come up with instructions to confidently reproduce the issue. Dealers seems to be dodging the questions around this, Toyota thinks swapping the differential is going to fix the issue, and we're essentially left to figure things out on our own. Would be curious to get a master spreadsheet going and to start compiling this data. Shimmy yes or no, list mileage and trim, 4wd yes or no, TSB done yes or no, lift/tires/modifications. I think part of the issue is being able to visualize this crap in single place to really narrow down based on patterns and commonalities.

 

Seems like I'm probably off my mark here then with the needle bushing.....

https://www.4runners.com/threads/ecgs-bushing-done.24261/


Idk... Still not convinced they CAN'T affect each other (needle bearing and wheel shimmy). We'll find out.... Oh will we find out

 

Does anyone make a strut tower brace for the 4R. Anyone tried that, perhaps on the Tacoma side? That would be a relatively cheap and easy experiment. My gut tells me this sensitivity to balance sits either in the frame or suspension mounts or steering rack.

 

The TSB isn’t for the shimmy. It’s for the needle bearing growling humming vibration. Whole separate issue.

 

Okay, mine did this on the test drive with the stock tires. When I had tires replaced, it still did it. Both at 32psi. Bumped the tire pressure up a couple of pounds, problem went away. I originally bumped up to about 40psi or so, and recently brought it down to around 34-35psi. I can occasionally *barely* feel it depending on the road conditions, but mainly no.

Sometimes tire tread pattern is just flaky. Had a similar problem with my VW and a certain brand of tires. They shook ridiculously at a certain road speed now matter how many times they were balanced and aligned. Just a weird resonance. With just a couple extra PSI, my KO2s are behaving admirably.

I'd try the cheap and easy thing first before going through all the trouble of pissing yourself off and going to yell at a dealership guy.

 

Mine had a shimmy from the very beginning with stock tires.

Put a lift on at about 5,000 miles. Still had the shimmy.

Replaced the tires around 10,000 miles with 285 Firestone Destination A/T's. Shimmy went away and I haven't dealt with it since.

Everyone already knows I think it's a wheel balance issue, but more specifically I think it's a tire "out of round" issue. I think we're putting a bunch of tires on that are not perfectly round to begin with and for some reason, the 4Runner is very sensitive to it. Could the sensitivity be related to our hub centric wheels? I'm not sure.

To put a value whether your tires are good or not, you need a Road Force Balance. They will give you a number for every tire they test. If a tire shows a Road Force number higher than 20 and they can't do anything to get it lower, that tire needs to be rejected and replaced with a tire that will go below 20. Once they are all below 20, they need to be maintained with a proper balance on a regular basis.

 

I never experienced the vibration until I installed my 1" bora spacers. I know that spacers can magnify existing balance and vibration issues. I have had a road force balance but no figured were provided. Guess I should look at that again. My shimmy is hit and miss. Today it popped up after they were warm (112-118 degrees at around 41 PSI once hot / set to 37 - C load BFG AT KO2's) so the whole tires will settle once warm is not really sticking.