I just returned from a 1 1/2 hour drive to my nearest Lexus dealership in my 2021 GX 460 with 29K miles. It squeaks at every speed over speed bumps, potholes, bridge transitions, etc. The dealership diagnosed it as “normal noise on vehicle equipped with kdss”. Can anyone confirm or deny that this is a legitimate diagnosis? Sounds more like a ball joint or strut issue to me.

 

On my 2021 I have not heard any squeeks, rattles or noises.
I would say your dealer is full of BS

 

Update on KDSS. I installed the Dr KDSS bypass. Installation was easy. About 30minutes, but I took it slow taking off the panels and wiring. I drive on road and the change is significant. Disabling KDSS results in a much more compliant ride on all road surfaces, like a real luxury car. Small bumps and imperfections are essentially gone. Biggest difference is rough road on one side of the car, these are absorbed much better with much less body shudder as you go over resulting in a very comfortable ride. It works fine on the highway as well, both small and large bumps and dips are reduced significantly. Of course turning has more body roll, but it in no way feels unstable. If you are driving leisurely or not hustling through tight turns no problem at all. If you are pushing it, reengage KDSS. It’s an excellent upgrade. It transforms the ride. It essentially reverses the use of the suspension. I run it disabled most of the time for comfort and engage KDSS like a sport mode for better cornering at speed. On my 2023 on first use it gave a Kdss error on the screen, but once dismissed it never came back with repeated use. Install is very simple and if you do not need the switch to be lighted, then you do not have to splice into any OEM wiring at all, it would be fully reversible. I would recommend getting the switch they sell as well as the new fuse box cover as the original will not fit with the add a fuse. You can really tell just how stiff and beefy the sway bars are on this vehicle. KDSS off reduces fatigue on long drives significantly.

 

It is good idea to at least annually clean out and apply a protective film to the KDSS accumulator. Debris does collect there. The cover is easily removable.

 

Sounds like the dealer is not top shelf. My first GX was silent, no chassis noise. Sold it at 166k miles. My wife’s 2017 Luxury is also silent with 100k on it now.