Ballancing your tires would be my first thought, sometimes that will create issues. Or maybe a bad tire too.
GX550 Overtrail Vibration
- Thread starter connorville
- Start date
In case anyone is worried, this seems to be a very isolated issue (possibly the only example). There are now many OT and OT+ deliveries with no issues, including mine.
This and the "Stop Sale" posts are the 2 most popular threads on this forum. I read both posts before I took delivery and was very concerned.
This and the "Stop Sale" posts are the 2 most popular threads on this forum. I read both posts before I took delivery and was very concerned.
The on / off nature coupled with the fact different wheels & tires hasn’t fixed it leads towards a suspension related cause. Also seems more OT models have the vibration which might indicate a KDSS problem.
I have been in my OT for a week now and the suspension, transmission, engine, and ride are as smooth as butter so far. I have no doubt there is a small select unfortunate few that are having weird vibration issues that can’t be diagnosed or resolved at dealer. I suspect this is the case with a lot of high production vehicles. There will always be lemons and a few bad apples in the bunch.
If this were a widespread problem, every 550 owner would be complaining about it.
TEST DRIVE your allocation before you sign!
If this were a widespread problem, every 550 owner would be complaining about it.
TEST DRIVE your allocation before you sign!
- Thread starter
- #125
5k mile update: Vibration is mostly noticeable from the first few minutes of driving. Mellows out throughout any trip. I am not sure but it seems that the KDSS seems to recalibrate every time you turn the car off and on. We can be on a trip to and from Houston and enter a gas station slowing down to <45 mph and feels better than it does when you start the vehicle and begin driving back onto the freeway after filling up. Sometimes it is pretty prevalent though after you have been driving for several minutes to several hours. It really is not consistent in that regard. However, it is consistent that vibration occurs every time you drive....
Still no resolution from the Dealer. They have gone pretty quiet since Lexus Corp closed the ticket saying it was "normal operation." About to take the vehicle in for its first service (oil change) and will ask the service director if they have had more people complain and brought the vehicles in for the same issue. I will also ask the GM and our sales guy if they have heard anything.
I am happy to hear that we are not the only ones that have this problem but also sad that a lot of owners are experiencing the same issue. I am hoping that with so many complaints and tickets sent in to 1800 LEXUS that they will issue a recall and have some sort of resolution.
Still no resolution from the Dealer. They have gone pretty quiet since Lexus Corp closed the ticket saying it was "normal operation." About to take the vehicle in for its first service (oil change) and will ask the service director if they have had more people complain and brought the vehicles in for the same issue. I will also ask the GM and our sales guy if they have heard anything.
I am happy to hear that we are not the only ones that have this problem but also sad that a lot of owners are experiencing the same issue. I am hoping that with so many complaints and tickets sent in to 1800 LEXUS that they will issue a recall and have some sort of resolution.
Sorry to hear of so many folks having the vibrations. Our GX is not here yet. would it help to diagnose the source of the vibration by putting the vehicle on a wheel dynomometer where only one axle is turned by the drivetrain and the other axle could be lifted off the floor to allow the all wheel drive to continue. Surely some service folks could get a little more involved to locate the issue. It could be just a flimsy metal on the hood or some unusual air flow like from the turbochargers air intakes which are fairly unique to the model. Again hope all of this can be solved for everyone.
The two post above are talking about two different vibration issues, correct? I don't have a GX yet but hopefully these two issues will be long past away.
Well they could be separate or the hood flap could be a result from drivetrain, I do not own a GX yet just trying to think about causes.
Interesting info here. Confirms my suspicions about KDSS. Sounds like the shock valving is “going stiff” intermittently. Time to dig deeper about how this system works. I have extensive experience building & servicing off road motorcycle suspension but know zilch about the KDSS setup.
I have the exact same issue going on as well. I know 100% it must have something to do with the KDSS or AVS. Just had a new set of after market wheels and tires put on yesterday, road force balanced and alignment done as well, running at 36 psi. I even asked the tech for the road force reading and they are all almost perfect. Havent been to the dealer yet, since I saw so many people post about getting tires rebalanced and all that. I knew that wasnt the issue, this feels like something suspension related. My OT is actually .25-.75 different heights on each side. Im coming from a 2022 Ram 1500 with a lift and off road tires, and it rode significantly better than my OT. Going to call Lexus shortly and file a complaint. I would say probably more to do with the AVS as it seems like it could be related to the rebound in the shock. But who know. Please keep this forum updated, Im very curious to see if/what the fix will be.
I’ve reached out to “Tinkerer’s Adventure” to see if he can weigh in. He has extensive knowledge on Toyota/Lexus suspension. In addition I’ll research more over the weekend about how this system works. We’ll figure it out…
Cool man, thank you!
Pardon my naivety in what I’m about to write. I watched just about every in depth review on YouTube and I havnt run across anyone talking about these issues. I’m guessing the vehicles they are testing have been put through the wringer. Do you think there is a possibility that there would be a “break in” period for the kdss system? Allowing things to kind of smooth out? Or on the converse does more “activity” make the vibrations worse?
No on the break in period. I’ve driven two GX 550’s 1 OT and 1 Lux. Neither had the issue these forum members are dealing with. Some of the felt vibs are subjective depending on your tolerance etc. but I’m siding with the idea somethings not right with these few GX’s.
The problem sounds like what you would get with one wheel a different diameter than the others friction being created in the driveline.
After doing more digging the shocks themselves do not have variable damping and current KDSS is only affecting sway bar disconnect and is fully automated. Not seeming like it has any bearing on ride quality other than increased articulation. My next thought is to pull and test each shock for proper function. It would be a compression vs rebound related issue that would explain the bone jarring type vibs. PITA but obvious next step. Fairly certain the shocks are made by Hitachi and are the Tokico line.
Sorry, first vehicle with KDSS or AVS. I thought the OT and OT+ came with AVS, so wouldn’t they have to have dampers?
Actually you’re correct! further research found this: https://www.caranddriver.com/news/a61162471/2024-lexus-gx-suspension-tested/#
Clearly the model Tokico shock on the OT is adaptive. Now we’re getting somewhere. This the most likely culprit for the rough ride being experienced by a few. See in the pic below the wire coming from the top of the shock.
Anyone with the issue should take it in and have the AVS tested. Hopefully it can be handled by a re-flash or module replacement vs all new shocks. Hope this helps…
Thanks for looking into it. I was going to reset the ECU first to see if that helps with anything. I saw somewhere to disconnect the battery and pull the ETCS and EFI 1 fuses, and see if that does anything.
