So I thought this trail edition 4Runner was a little stiff on washboard roads when stock, but it wasn't gonna stay that way for long... I've got an icon stage 2(650lbs front spring rates) lift kit with the track bar and a perfect alignment afterwards, the route I took with the kdss was to strap the cylinders in place before jacking it up then remove the sway bars, did the lift, put it down and hooked up the sway bars and took the straps off, everything was fine, kdss moves and works like it should, sway bars are level, did the bleed procedure anyway, no air... I do a LOT of Offroading and have years of experience on my own time and in competition.
The thing works great at low speed like 6mph and under, long travel shocks, tires stay on the ground, articulation is great!, I'm running 16psi in the tires but I'm typically going around 15mph on a lot of Stoney or washboard roads and it feels as stiff as a sports car, just like on the street.... my take on this is it needs a much smaller sway bar or the valving in the accumulators needs to be changed for easier movement... I thought it might be the shock valving or spring rate not matching the kdss movement but at higher speeds the shocks work great and I don't want to chance bottoming out if I make a shock valving adjustment + vehicle down time while the shocks are sent out.. Does anybody else with a lift and kdss feel the same rough ride at medium speeds offroad? And are there smaller sway bars out there for kdss? if you have any real experience with your own similar set up please respond.. Thanks 👍🏼

Nope.

the KDSS "open" mode cutoff is 12 mph. when the ECU sees the vehicle is traveling faster than that, KDSS operates in "closed" mode, firming up sway travel and buffering small impacts via the accumulators.

since you've got 255/80s on, your speedo is under-reporting your actual speed, so when you say 15 mph it's probably more like ~16-ish mph (speedo over-reports with stock tires) so you're well out of specified range for KDSS to operate in open mode for free travel of the swaybars.

try driving more slowly and see how it feels. keep it under 10 mph. like you already said, it works works great at low speed like 6 mph... you're just going too fast.

agree noticed the same thing with mine. slowing down a bit did wonders.

Or better yet, figure out where to splice a switch to activate KDSS on demand, take lots of pics for a noob friendly thread!

Otberwise we'll have to stick with what Toyota wants us to get.

hmmmmmm good idea

What you are experiencing is pretty common. It's one of those cons of KDSS and another reason I think they did not put it on the TRD Prod.... Even though I'm not a high speed wheeler, I've been surprised how stiff they are at moderate speed with a lift. It's not that bad stock, but the front swaybar is a bit bound up when you lift it. We tried to troubleshoot one and finally came to the conclusion of "it is what it is"...

I really doubt you will ever find another swaybar for it (you would have much better luck finding a pink unicorn). Another option is trying to lower the mounts in the front (that is where most of the problem is IMHO). The juice did not look worth the squeeze though.

The thought I had was trying to figure out how to wire in a bypass switch of some sort. That would work fantastic and should not be that difficult to figure out.

And there is always the nuclear option... Just remove KDSS throw on LT and have a truck that will actually eat up the trails at speed.

Makes perfect sense!! I need to figure this out, do you know if kdss will work if it's simply unplugged somewhere?, a bypass ground switch would be an easy fix.. Driving slower than 10 isn't really an option considering the washboard roads are already a 45min drive to the good trails and that's doing around 30mph... If I can get anymore info or links to what other people did I will gladly edit a YouTube video for the fix.. I just don't want to waist my 1300$ option and have to go buy a regular swaybar kit.

Would be awesome if someone came up with that bypass switch. I really like what KDSS does on the road, and at low speeds off road. However, I do like to go fast off road too. I prefer fast flowy non-technical trails to rock crawling.

i'm not sure it would work if it was simply "unplugged". it'd at least throw a code or ten and not certain what state it would put/leave the system in. there's a wiring harness on the right side of the KDSS housing and accumulator assembly (outside driver frame rail) and you can get the complete vehicle wiring diagram and trace out the paths.

i would think there might be some clever hack to trick the system into staying in "open" mode as you desire (e.g., via switch) in the same way you can hack a reverse camera or override the vehicle-in-motion lockout on the factory Nav. it hasn't been done, to my knowledge.

i do know that you won't be able to buy a "regular swaybar kit" either, as the mounts are not the same and specific to KDSS.

I don't rightly know if kdss would affect ride over washboard. The larger anti roll bars fitted to the kdss truck should have a larger affect over moguls at speed than washboard. As long as both wheels on a given axle hit a bump at the same time the anti roll bars, whether a kdss or a regular setup, would not play a part in the equation. My gut would tell me to look at the tires (sidewall stiffness) or the shock valving which may not be set up ideally for quick, short, repeated movements. Idk, just how I feel about it. Hope you find a resolution.

That's what I thought, but when hit perfectly even it rides fine, most of the stones are not hitting at the same time and I've felt like the ride just gets stiff at medium speed and now knowing the kdss switches right about that speed I felt, I know it's the kdss that needs adjusted..

Next question! How do I check or reset engine codes??
I'm gonna try unplugging it first just to see what that does

if you want to fix washboard comfort that is shocks/springs and tires

This washboard isn't perfectly even and I'm at 16psi, tires can stuff to the fenders at low speed, do some research on stiff sway bars man.