Dan Edmunds take a deep dive on GX550 suspension
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Watch it yesterday and was really surprised it gives less flex than LC250 with swaybar disconnect.
It should be a lot better on road as it would be relaxed when it did not sense the car is turning and need the solenoid to be closed. High speed cornering is where KDSS usually shines.
It should be a lot better on road as it would be relaxed when it did not sense the car is turning and need the solenoid to be closed. High speed cornering is where KDSS usually shines.
Having removed KDSS from my 4runner and testing it extensively both ways, I actually figured the difference would be larger in the favor off the swaybar disconnect.
I'll take a disconnect or smaller traditional sway bars over KDSS any day.
I'll take a disconnect or smaller traditional sway bars over KDSS any day.
How they are disconnected is another issue but the 250 only does the front and the GX can do the rear – what am I missing about the benefit of that in the real world driving over uneven trails?
I'm not smart enough to understand the why, just my observations, is that the rear swaybar doesn't make much, if any difference on flex. Not sure if it is because of the solid axle, the way the links work, or what. Disconnecting the front swaybar makes a massive difference. Driving on road is similar, the rear swaybar makes a small difference in body roll, the front makes a huge difference.
Main reason I removed mine was the terrible ride quality at medium/high speeds on bumpy dirt roads.
I feel like the flex-test numbers difference is an increasingly diminishing return in the real world as the number goes up. Like the LC200, LC250, and GX550 all have way higher scores on the ramp than a Sasquatch Bronco but the Bronco is a much better rock crawler stock than any of them. It's a neat way to try to consistently measure articulation, and it's fun to see everything climb the ramp, but it's not the end-all be-all of off road prowess. In the real world, I doubt the difference in measured flex between the LC250 and GX OT would be noticeable.
Someone (Edmunds.com I think) recently had an off road comparison of the 2 and the main differences they noted were the LC250s better approach angle/shorter nose and the GX was better at higher speed stuff. Both handled everything very well. I haven't seen any comparisons or videos where anyone calls out a noticeable difference in flex during actual driving - we will have to wait for Tinkerer's Adventures to get his hands on both.
Does that center bracket on front KDSS reside on fairly stout piece of frame?
I’ll gladly join the not so smart club but there have been a couple of pictures posted here showing impressive rear flex by a GX OT, which I assumed was only possible because of E-KDSS
Fort9378
SILVER Star
KDSS has never been about stretching the extremes of suspension flex. It's just conveniently engineered to be adaptable across multiple speed/uses. A KDSS equipped suspension doesn't magically travel more than any other suspension. Jeremy is right in that rear swaybars have basically no effect on overall flex numbers. I believe tinkerer adventures addresses that in his KDSS video.
I believe the main advantage of KDSS over the disconnects is that generally swaybar disconnects re-engage when going over a certain speed. Whereas KDSS adjusts based off of the speed, going higher than disconnects do. I could be talking out of my rear end though.
I believe the main advantage of KDSS over the disconnects is that generally swaybar disconnects re-engage when going over a certain speed. Whereas KDSS adjusts based off of the speed, going higher than disconnects do. I could be talking out of my rear end though.
My experience with body flex off-road is…. I don’t want it to flex at all.
I usually have a lot of heavy gear on the roof rack and a flexy suspension when driving off camber means the body will lean a LOT more towards the downside — imperiling a rollover.
If the suspension is not twisty, the body stays more upright. Way safer.
Also…. When the vehicle gets on a sideways slant (off camber) the high side has minimal traction anyway because all the weight is on the low side.
So what if the high side tire is just touching the ground? Its not doing much of anything anyway.
I guess driving over a single big rock might benefit from a twisty suspension because both axles aren’t being lifted simultaneously- but get sideways on a downhill slope? Watch out!
At least that’s my experience
I usually have a lot of heavy gear on the roof rack and a flexy suspension when driving off camber means the body will lean a LOT more towards the downside — imperiling a rollover.
If the suspension is not twisty, the body stays more upright. Way safer.
Also…. When the vehicle gets on a sideways slant (off camber) the high side has minimal traction anyway because all the weight is on the low side.
So what if the high side tire is just touching the ground? Its not doing much of anything anyway.
I guess driving over a single big rock might benefit from a twisty suspension because both axles aren’t being lifted simultaneously- but get sideways on a downhill slope? Watch out!
At least that’s my experience
This! KDSS lets you run big, stiff sway bars which are good for cornering stability at speed, but then basically unlocks/disconnects those bars by default at low speed so you maximize articulation within the stock geometry. I think the big improvement from hydraulic KDSS to the new E-KDSS is that E-KDSS should react much faster and is independent F/R. That should make a much improved ride on rough surfaces at mid speeds like a 25mph cobblestone street, and eliminate KDSS lean as a thing.
Fort9378
SILVER Star
What? That's the exact opposite of how an offroad suspension works. If all 4 wheels are on a grade, sure, maybe. If you're putting one tire/side over a rock or obstacle and you don't have suspension flex then your whole vehicle is going to roll a lot more than if the suspension just flexed over it.
SanJuanJ
SILVER Star
How did you do this? Is it easily reversible if you wanted the KDSS again?
Physically removed the front swaybar. It's been probably 4 years now and I have no plans of going back, but it would be as easy as re-installing it.
Interesting how 'Previous KDSS' is lower, yet the 2021 200 scored higher on the RTI than the GX 550 (and LC 250).Tinkerer did mention that he would do a video comparing the two, which will be interesting.
Until then....
I do think people can get lost in the RTI numbers and the real-world application. If you're crawling in a 100/150/200/250 then you're the outside use case. Honestly, a Jeep is much better for this purpose. The KDSS is beneficial in two ways: 1) comfort and 2) passive. A disconnect is great, but if you are in continuously varying terrain the need to lock/unlock the swaybar is a hassle. Have not used on the 250, but in the Ram this isn't instant. The system needs to be unloaded and aligned to get things to move. Further, (in the Ram) it passively reconnects at 19 mph. So if you have a mixed-condition trail you're cycling it often. But more importantly, the E-KDSS should reduce driver fatigue. In a 'touring' overlander I'll take this over a few points of additional limit travel any day. Focus on what aligns to your primary mission.
The one thing I haven't seen yet is what a lift looks like on the GX550. I'm assuming this would need to be a space lift, either at the top of the spring or above the strut. This isn't AHC where you can adjust the sensors to get you an extra inch or two.
What also interests me is how well AHC performed on the LX600; I'd love to be able to sample both AHC and eKDSS back to back.
It looks like the new E-KDSS should be more conducive to a lift than the outgoing version. E-KDSS has 2 rams up front that attach via short end links vs the 1 ram, 1 fix link and direct LCA attachment of the 460's KDSS. So you just need extended end links instead of all the spacers/brackets necessary on the 460. I think for the rear axle you would also just need some kind of spacer for the sway bar to match the lift.
You will lose adaptive dampers if you lift with shocks/springs but that has been the case for the 470 and 460 for the last 20 years. It would be rad if someone made a kit that would keep the adaptive connection using Fox Live Valves or Multimatic dampers like the ZR2 Chevy trucks but that would be $$$$.
