KDSS / Mod Hell - Rant!

Bottom line is whatever approach you decide to go with, give yourself latitude during the install to correct any resulting lean. RSG has the capability to fabricate engineering plastic top spacers on site for custom lean correction, and they are familiar with a KDSS. PM me if you have any questions.


Thank ya kindly. I may reach out once I'm out there. I'm certainly not looking for anything huge maybe just an inch or two eventually. As I mentioned I'm new to the forum so I doubt I'll be able to feel out all the issues and intricacies that a more experienced T4R owner would.

I have heard Slee is familiar with KDSS and is a very respected shop here in Colorado. If you are looking for someone to work on your KDSS runner that would be a good place to start. ToyTec while very nice and helpful does not do installs.

Thanks Mike! Good to know ablut Slee, I'd come across RSG in my searches but not Slee so thank ya. Also a little bummed Toytec doesn't do installs. Figured if I could go right to the source they'd know how to handle things. Thanks again!
 
As [MENTION=164114]TEujunga[/MENTION] points out, you shouldn't be alarmed or generating any angst about your purchase due to my whining (aka "Crank").

LOL! You'd have a ways to go before you qualified as a true "crank," IMHO, but if you were actually to sell a truck you love merely because of an intermittent 1" KDSS lean, it would be a step in the right direction :)
 
RSG is a Toytec dealer, and Toytec refers people to RSG all the time for installs. Slee is great, but they aren't fans of spacer lifts (at least in front).
 
Had all final mods for this year done on mine this June and it is equipped with KDSS. Am very happy with how it handles on and off-road and towing and I do go out whenever I have free time here in the Rockies to explore trails that many would not. 1/4" difference from driver to passenger side with mine. Some members had mentioned in previous threads about modding a KDSS equipped 4-runner that if done right it will drive like butter. Gotta say I agree, have never enjoyed a vehicle as much as this one. :)

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To correct some possible misinformation here:

KDSS is on every flagship Toyota SUV. The flaghship 150 platform is either the GX460 in the USA or the Prado 150 Kakadu. The LC200 also has a more advanced version of KDSS.

KDSS was left off the TRD Pro for unknown reasons. Toyota's not exactly an open book on these things. It was on the original TRD Pro concepts, but not on the final cut. It was used on Toyota's Baja 1000 4runner - which they modified the suspension and could easily have removed. It does not overheat. The shutter valves close at 12mph. My personal opinion is that it was simply a pricing issue. Keeping MSRP of the TRD Pro under the Limited meant removing KDSS. There's an argument that it effectively provides a stiffer individual corner effective spring rate that reduces the compliance in fast uneven terrain - basically the sway bar is too stiff for high speed desert use. I'd love to compare side by side with a TRD Pro on a desert course, but I don't have one.

KDSS has one major design flaw - it uses single acting cylinders. Single acting cylinders have net volume differences depending on level of extension. This combined with medium pressurized hydraulic system results in a net force on the cylinder that is dynamic with position - the further extended the the cylinders are, the less net static force )force pushing down as a result of pressure, not as a result of operation) they have (because the pressure goes down with volume change). In a perfect world Toyota would solve this by using 4 cylinders, or two double acting cylinders (like mclaren does).

Toyota has used a variety of springs in the 5th gen with KDSS. Up until about 2015 the KDSS 4runners had unique front and rear springs that were specific side to side. After 2015 I believe they used the same springs as the other 4runners. I don't remember if they are side specific post 2015.

Adjustable aftermarket lifts should sit reasonably level. Within 1/4 side to side.

If you're building a hardcore off-road 4runner with more than about 3 inches of suspension lift - KDSS is probably best left off the option list unless you want to do more complex engineering than most aftermarket companies are likely to do. A moderate 2-3 inch lift should be pretty easily accomplished while retaining the benefits of KDSS.
 
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As a recent buyer of a 2017 Trd Premium with KDSS I wish I hadn't come upon this thread. Because I would love to lift it a little bit, and have it for a long time. I hope the truth lies somewhere in between both extremes of this argument and I can gain a little height without coming into big problems.

Is it possible as time goes on and shops/mechanics gain more experience the familiarity with the system within increase?

I'm moving out to Denver in October and was excited to find out Toytec is based there. Hoping if someone could point me in the right direction along with this site it would be them. Any thoughts?

You can chose to take this info with a grain of salt, but when I was shopping for my 2017 4runner, I knew that I would be lifting it, and that my dealer would likely being doing the install. They are a stocking dealer for Toytec, King, and Icon suspension among others.

When I asked them about whether lifting / modifying a KDSS vehicle was a bad idea, they told me they were a little leary about it on the first few they modded (years ago), but in the long run they haven't had any real issues.

As a backup, I called Toytec and asked them the same question. Their response was if they were buying a new 4runner with the intention of doing mild mods (Toytec 2.5 BOSS suspension in my case), the WOULD get a KDSS equipped vehicle.

As an aside, I've had my lift on for ~3,500 miles and have zero noticeable lean...and I'm pretty OCD about things like that.
 
When I asked them about whether lifting / modifying a KDSS vehicle was a bad idea, they told me they were a little leary about it on the first few they modded (years ago), but in the long run they haven't had any real issues.

As a backup, I called Toytec and asked them the same question. Their response was if they were buying a new 4runner with the intention of doing mild mods (Toytec 2.5 BOSS suspension in my case), the WOULD get a KDSS equipped vehicle.

As an aside, I've had my lift on for ~3,500 miles and have zero noticeable lean...and I'm pretty OCD about things like that.

This is music to my ears. I'm not in a huge rush or need to get it done soon I just want it done right when I decide to go for it. I see you're out in Durango. I'm moving to Denver in late October maybe we'll cross paths! I'm pre-novice in this world but have been stuck in the middle of Philadelphia for so long I can't wait to get out and see some of the country in the 4Runner.

Cheers
 
KDSS PISTON leaking into boot and now tiny bumps are loud, no lights yet but just curious if anyone knows about repairing? I’m doing bushings and tie rods in a couple weeks when my parts arrive. Over 100,000mi and this is the FIRST issue I’ve ever had with her. Also, spoke with multiple Toyota and Lexus dealerships in my are and they have NO idea what I’m talking about LOL.


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I have a 2016 TE with KDSS and for my planned use seems perfect. As a beginner I only go on easy to moderate trails and the stock configuration has performed flawlessly with stock size BF K02's. I don't ever plan to lift it since it seems sufficient for my needs and I just think a lower center of gravity is a safer vehicle. I do like the stance when accelerating around a bend which I guess is partly due to the KDSS and K02'. Who knows what the future holds and maybe some day I will want to advance beyond this.
 
My rig has had zero issues in a couple thousand miles after adding a dobinson lift, UCA’s, and a set of Treaty Oak KDSS spacers. I’m lifted about 2.75-3” all the way around.

I really like the concept behind the T.O. KDSS spacers. Does your icon kit include them? Or does it account for the system a different way?

It appears my dream truck is turning into a game of Whack-A-Mole and I'm convinced that KDSS is a huge mistake for anyone modding their 4Runner.

After having my new Pelfrey aluminum bumper and winch installed the front to rear rake and side to side unevenness is just too much to accept. I'm sure the added 135# is contributing to the dip in the front and I'm having my Icon's adjusted next week to accommodate that. I'm also having the alignment redone due to some weird inside tire front right tire wear that preceded the bumper install. I suspect the KDSS lean is contributing, at least in part, to this wear.

The KDSS lean is especially driving me nuts. I'm sure it will only get worse with me adjusting the front shocks to adjust for the front dip. Hopefully, I can get some good advice or words of encouragement because, I'm honestly considering taking all this stuff off my truck and selling it and the truck too.
 

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