09-15-2020, 09:30 PM
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#2
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Banned
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Join Date: Mar 2018
Location: Arizona
Posts: 1,612
Real Name: Tobias Fünke
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Banned
Join Date: Mar 2018
Location: Arizona
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Real Name: Tobias Fünke
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Quote:
Originally Posted by phey_05
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@ Jetboy
to the rescue...
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09-16-2020, 02:04 AM
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#3
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Senior Member
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Join Date: Jun 2013
Location: Bay Area CA
Posts: 1,811
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Senior Member
Join Date: Jun 2013
Location: Bay Area CA
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Sorry to hear this, but it is why they produce that product. I’d find the highest rated differential shop in town and trust them with the install. Technically it’s not that hard so I wouldn’t worry too much. Local input from the community here should steer you right (no pun intended).
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09-16-2020, 09:04 AM
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#4
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Member
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Join Date: Jul 2016
Location: Virginia
Posts: 536
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Join Date: Jul 2016
Location: Virginia
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if you havent had it roadforce balanced by someone that has a clue, do that first. then check out your lower control arm bushings--have someone turn your wheel lock to lock when parked and look for unacceptable play. This ended up being my issue--after i switched to dirt king LCAs, my issues went away.
The bushing is interesting, but it seems that it didnt work for some folks on that thread
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09-16-2020, 10:42 AM
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#5
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Member
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Join Date: Sep 2016
Location: Houston
Posts: 35
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Join Date: Sep 2016
Location: Houston
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Quote:
Originally Posted by JSparky
Sorry to hear this, but it is why they produce that product. I’d find the highest rated differential shop in town and trust them with the install. Technically it’s not that hard so I wouldn’t worry too much. Local input from the community here should steer you right (no pun intended).
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Thank you Sir, I'm searching for a good differential shop now and hopefully someone can refer me to their trusted shop.
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09-16-2020, 10:44 AM
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#6
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Member
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Join Date: Sep 2016
Location: Houston
Posts: 35
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Join Date: Sep 2016
Location: Houston
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Quote:
Originally Posted by tm965
if you havent had it roadforce balanced by someone that has a clue, do that first. then check out your lower control arm bushings--have someone turn your wheel lock to lock when parked and look for unacceptable play. This ended up being my issue--after i switched to dirt king LCAs, my issues went away.
The bushing is interesting, but it seems that it didnt work for some folks on that thread
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Good to know! All along my mind is set that it's the bushing.
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09-16-2020, 12:28 PM
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#7
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Member
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Join Date: Jul 2016
Location: Virginia
Posts: 536
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Member
Join Date: Jul 2016
Location: Virginia
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Quote:
Originally Posted by phey_05
Good to know! All along my mind is set that it's the bushing.
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could be, interested to hear how this works out for you.
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09-16-2020, 12:53 PM
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#8
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Elite Member
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Join Date: Dec 2014
Location: Utah
Posts: 5,020
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Elite Member
Join Date: Dec 2014
Location: Utah
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FWIW - I have had the bearing go bad. It did not cause any front end shimmy. The shimmy is usually related to tire balance and/or suspension issues. The best fix I've heard of is to replace the pressure spring in the steering rack with a stiffer one. That's how Lexus fixes the GX shimmy. Toyota apparently will not do the same warranty fix. They are the same steering rack BTW.
If it's the bearing - it goes away in 4hi and comes back in 2hi. Try shifting between the 2 at 40mph and see.
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09-16-2020, 10:38 PM
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#9
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Member
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Join Date: Mar 2014
Location: Kansas City, MO
Posts: 378
Real Name: Jeff
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Join Date: Mar 2014
Location: Kansas City, MO
Posts: 378
Real Name: Jeff
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My experience with the ECGS bushing was positive. It didn’t completely get rid of the front end vibration but did significantly reduce it.
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Last edited by Cisco Kid; 09-16-2020 at 11:02 PM.
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09-17-2020, 09:35 AM
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#10
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Elite Member
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Join Date: Dec 2014
Location: Utah
Posts: 5,020
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The steering rack spring is basically just a small coil spring that applies a spring force to a bushing that pushes on the sliding shaft in the steering rack. It's function is to take up any slack in the system and it acts in some ways like a dampener in the system. More dampening seems to eliminate the steering shimmy. Here's a picture of where it's located. I'm not sure that helps much because I'm not sure if you can buy the firmer spring used in the GX. But that's the TSB fix for Lexus. Toyota's fix for non-lexus models is mostly to pretend it doesn't exist.
It's the result of something in the suspension design that causes a harmonic frequency to build and feed back through the steering system. It's been an issue on BOF toyotas for a very long time and Toyota hasn't fixed it for some reason. It's not common - but also not really rare. It also can usually be fixed by adjusting alignment - meaning real adjustments like adding 1* or removing 1* of caster. It's not necessarily a need to go one way or the other - it's a matter of changing geometry slightly to disrupt the cyclical frequency so it doesn't reach a harmonic feedback state. It could also probably be fixed with a small change in toe, or by swapping out the lower control arm bushings to bushings with a different density of rubber. Or many other options. They all just disrupt the cyclical feedback frequency.
In the picture below you can see where the spring is located. It's hard to access in the vehicle. The large allen key style machine screw threads into the housing and it applies pre-load. You can simply adjust for more preload too to add some preload. Don't go overboard on this or you could cause it to bind up. Then re-tighten the locking nut. This is a common fix on worn out 3rd gen 4Runner steering racks to tighten them up after 200k miles. I've done this myself on my last 3rd gen. It was really easy to access on those models. It's hard to access on the 5th gen.
Inside that thing I pointed to is this:
Here's the exploded view.
And you can see the small spring. That's what Lexus swaps out for a higher spring rate. If someone wanted to do some research - take the spring out, measure the spring rate, then we could probably pretty easily find an off-the-shelf industrial supply spring to replace with to replicate what Toyota uses to fix it. A replacement spring would probably cost less than $1 each. (You could also find an ECGS bushing for around $1 each from an industrial supplier too, they just mark em up about 1,000%).
Hope that helps point you in the right direction for a fix.
Balance your tires. Make sure your suspension is all in good condition. Then I'd start looking for an alignment shop to play with the setup a bit until you find a sweet spot that doesn't shimmy.
Last edited by Jetboy; 09-17-2020 at 09:49 AM.
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09-17-2020, 09:52 AM
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#11
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Member
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Join Date: Mar 2014
Location: Kansas City, MO
Posts: 378
Real Name: Jeff
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Member
Join Date: Mar 2014
Location: Kansas City, MO
Posts: 378
Real Name: Jeff
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Quote:
Originally Posted by Jetboy
The steering rack spring is basically just a small coil spring that applies a spring force to a bushing that pushes on the sliding shaft in the steering rack. It's function is to take up any slack in the system and it acts in some ways like a dampener in the system. More dampening seems to eliminate the steering shimmy. Here's a picture of where it's located. I'm not sure that helps much because I'm not sure if you can buy the firmer spring used in the GX. But that's the TSB fix for Lexus. Toyota's fix for non-lexus models is mostly to pretend it doesn't exist.
It's the result of something in the suspension design that causes a harmonic frequency to build and feed back through the steering system. It's been an issue on BOF toyotas for a very long time and Toyota hasn't fixed it for some reason. It's not common - but also not really rare. It also can usually be fixed by adjusting alignment - meaning real adjustments like adding 1* or removing 1* of caster. It's not necessarily a need to go one way or the other - it's a matter of changing geometry slightly to disrupt the cyclical frequency so it doesn't reach a harmonic feedback state. It could also probably be fixed with a small change in toe, or by swapping out the lower control arm bushings to bushings with a different density of rubber. Or many other options. They all just disrupt the cyclical feedback frequency.
In the picture below you can see where the spring is located. It's hard to access in the vehicle. The large allen key style machine screw threads into the housing and it applies pre-load. You can simply adjust for more preload too to add some preload. Don't go overboard on this or you could cause it to bind up. Then re-tighten the locking nut. This is a common fix on worn out 3rd gen 4Runner steering racks to tighten them up after 200k miles. I've done this myself on my last 3rd gen. It was really easy to access on those models. It's hard to access on the 5th gen.
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Clearly I’ve been living under a rock for a while or something. I knew about the front end vibration issue as mine has a bit of that but hadn’t heard about replacing the spring in the rack. For what it’s worth, I did find the Lexus TSB showing the process and it’s not something I care to attempt at the moment. There are actually 4 additional springs available to adjust the preload and those part numbers are in the TSB.
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09-17-2020, 11:27 AM
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#12
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Member
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Join Date: Sep 2016
Location: Houston
Posts: 35
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Member
Join Date: Sep 2016
Location: Houston
Posts: 35
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Quote:
Originally Posted by Jetboy
The steering rack spring is basically just a small coil spring that applies a spring force to a bushing that pushes on the sliding shaft in the steering rack. It's function is to take up any slack in the system and it acts in some ways like a dampener in the system. More dampening seems to eliminate the steering shimmy. Here's a picture of where it's located. I'm not sure that helps much because I'm not sure if you can buy the firmer spring used in the GX. But that's the TSB fix for Lexus. Toyota's fix for non-lexus models is mostly to pretend it doesn't exist.
It's the result of something in the suspension design that causes a harmonic frequency to build and feed back through the steering system. It's been an issue on BOF toyotas for a very long time and Toyota hasn't fixed it for some reason. It's not common - but also not really rare. It also can usually be fixed by adjusting alignment - meaning real adjustments like adding 1* or removing 1* of caster. It's not necessarily a need to go one way or the other - it's a matter of changing geometry slightly to disrupt the cyclical frequency so it doesn't reach a harmonic feedback state. It could also probably be fixed with a small change in toe, or by swapping out the lower control arm bushings to bushings with a different density of rubber. Or many other options. They all just disrupt the cyclical feedback frequency.
In the picture below you can see where the spring is located. It's hard to access in the vehicle. The large allen key style machine screw threads into the housing and it applies pre-load. You can simply adjust for more preload too to add some preload. Don't go overboard on this or you could cause it to bind up. Then re-tighten the locking nut. This is a common fix on worn out 3rd gen 4Runner steering racks to tighten them up after 200k miles. I've done this myself on my last 3rd gen. It was really easy to access on those models. It's hard to access on the 5th gen.
Inside that thing I pointed to is this:
Here's the exploded view.
And you can see the small spring. That's what Lexus swaps out for a higher spring rate. If someone wanted to do some research - take the spring out, measure the spring rate, then we could probably pretty easily find an off-the-shelf industrial supply spring to replace with to replicate what Toyota uses to fix it. A replacement spring would probably cost less than $1 each. (You could also find an ECGS bushing for around $1 each from an industrial supplier too, they just mark em up about 1,000%).
Hope that helps point you in the right direction for a fix.
Balance your tires. Make sure your suspension is all in good condition. Then I'd start looking for an alignment shop to play with the setup a bit until you find a sweet spot that doesn't shimmy.
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Im having a migraine by just reading this.
I contacted a high rated shop in my area, and the guy said, come and they will have a look, he said maybe it can be fixed by just an alignment, i told the guy that i've been to a 2 different alignment shop (in Houston, which is a year ago, and it didn't eliminate the issue). But he is eager to check it for me. Maybe ill consider this 1st as you suggested below, this issue always exist on my vehicle, its just that recently, in the middle of a 700 miles road trip, it became wild.
The shop by the way, doesn't have a road force balance, so we'll see.
Quote:
Balance your tires. Make sure your suspension is all in good condition. Then I'd start looking for an alignment shop to play with the setup a bit until you find a sweet spot that doesn't shimmy.
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Thanks for the input Sir!
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09-17-2020, 11:39 AM
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#13
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Member
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Join Date: Jul 2016
Location: Virginia
Posts: 536
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Member
Join Date: Jul 2016
Location: Virginia
Posts: 536
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Quote:
Originally Posted by phey_05
Im having a migraine by just reading this.
I contacted a high rated shop in my area, and the guy said, come and they will have a look, he said maybe it can be fixed by just an alignment, i told the guy that i've been to a 2 different alignment shop (in Houston, which is a year ago, and it didn't eliminate the issue). But he is eager to check it for me. Maybe ill consider this 1st as you suggested below, this issue always exist on my vehicle, its just that recently, in the middle of a 700 miles road trip, it became wild.
The shop by the way, doesn't have a road force balance, so we'll see.
Thanks for the input Sir!
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honestly dont even bother if the shop doesnt have a road force balancer. it is 100% necessary. it also helps to have a tech that cares/actually tries. the road force numbers on all tires need to be below 15, and the closer to 0 the better.
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09-19-2020, 10:27 PM
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#14
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Member
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Join Date: Sep 2016
Location: Houston
Posts: 35
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Member
Join Date: Sep 2016
Location: Houston
Posts: 35
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Quote:
Originally Posted by tm965
honestly dont even bother if the shop doesnt have a road force balancer. it is 100% necessary. it also helps to have a tech that cares/actually tries. the road force numbers on all tires need to be below 15, and the closer to 0 the better.
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Im in a hunt of a shop with road force balancer again.
I hope there's someone on this forum that is from SoCal that can give me a recommendation
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09-19-2020, 11:03 PM
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#15
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Member
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Join Date: Apr 2019
Location: Los Angeles, CA
Posts: 975
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Member
Join Date: Apr 2019
Location: Los Angeles, CA
Posts: 975
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Quote:
Originally Posted by phey_05
Im in a hunt of a shop with road force balancer again.
I hope there's someone on this forum that is from SoCal that can give me a recommendation
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Try RPM garage in LA
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2019 ORP - KDSS, Dobinsons C59-302/GS59-700 front and C59-725/IMS59-50701 rear, Dobinsons UCA, DuroBump/Daystar bumpstops, Sonoran Steel High Articulation tracbar, Marlin Crawler LCA frame brace, OGS Lo-Key Bumper w/ Warn VR EVO 10-S, RCI Sliders, fully armored with RCI/C4/Outgear Solutions skids, Falken Wildpeak M/T 285/70/17, LFD SS-Crossbars, ARB breather kit (Rear Diff and Locker), ScanGaugeII, Anytime Front/Backup Camera, onboard ARB Twin compressor MORRFlate kit, and DD SS3 Sport fogs
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