KDSS Stupid (1 Viewer)

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Yes I’m going to do it myself. Replaced KDSS unit because of rusted hex bolts. Called 6 dealers around my area and all 6 don’t know what KDSS do. Do you also know the SST tool part number for LC200?
I don’t, but it has been covered online elsewhere. Not too difficult to find. Same as on 4runners.
 
yes, significant lean after a lift by a competent shop with known kit (Dobinson) - but no known issues beforehand. clean CPO 2015 with 70k miles... after the lift was done, no matter of adjusting, blocking, etc corrected the lean. took it to the dealer and they only have one remedy - purge and re-pressure. The procedure mostly correctly the lean, but i also had to add a 1/4 spacer to the driver front to get it 100% leveled.
Which dealer did you use? I'll need that service done soon, I'm in Boston.
 
I have a 1” learn “drivers side”. Not sure I loosened the hex bolts enough as I raised the drivers side with the bottle jack with the tire off the ground about 2” and waited about 5mins and then tightened the bolts and lowered the truck. Nothing changed. What did I do wrong?
 
I have a 1” learn “drivers side”. Not sure I loosened the hex bolts enough as I raised the drivers side with the bottle jack with the tire off the ground about 2” and waited about 5mins and then tightened the bolts and lowered the truck. Nothing changed. What did I do wrong?
You didn’t fix the problem, which is probably with your springs.

Using the KDSS system to force a competing lean is not the right way to treat that system.
 
You didn’t fix the problem, which is probably with your springs.

Using the KDSS system to force a competing lean is not the right way to treat that system.
The springs are new but they might have put them on the wrong side. Anyway to tell? They are Ironman springs
 
The springs are new but they might have put them on the wrong side. Anyway to tell? They are Ironman springs
The lean is a good indicator.

Beyond that I’m not sure how Ironman springs are labeled, but even if they’re in the correct spot trim packers are a better way to address this than putting constant load on the KDSS hydraulic system to force the vehicle out of a lean caused by something else.

Our understanding of the system has come along since this thread started.
 
Taller spring goes on the passenger side

If your passengers side is still lower add a coil spring trim packer to level it
 
Taller spring goes on the passenger side

If your passengers side is still lower add a coil spring trim packer to level it
The driver side is lower of 1"
 
Maybe this is already covered in this thread or you all already know this, then please ignore. I did raise this in another KDSS or lean thread, yet it is worth reasoning through how it works and therefore what is happening. In short KDSS is not the root cause of lean. For those interested, the reason is explained below.

KDSS workings on a LC200
Not considering the KDSS setup on a GX which seems to get input from a sensor(s), our LC200 has a pure hydraulic system *) with actuators on the stabilizer bars per the diagram below (with the one front and rear actuator shown, as connected to our stabilizer bars). It works as shown with the two allen key bolts (or newer LC's hex bolts) in the normal turned in position.

*) as a footnote, there are some fluid expansion chambers on the unit in the middle, i expect their main function is to compensate for fluid temperature expansion and maintaining system pressure as a result, they i believe do not change the way the system works or my conclusion to resolve lean.

On road, when cornering the vehicle will lean to one side. This compresses the actuators in the same way/same sides either green or yellow and therefore they resist movement. It therefore greatly limits the lean in corners, coming around getting onto the interstate etc. This is great for an otherwise heavy and fairly tall vehicle. Love this aspect of KDSS, the main reason I will keep it in commission for as long as I can or will repair it. Essential to how the 200 drives unless you primarily offroad and do not care about onroad handling. I would argue that is very few of us, even "hard core" off roaders. Those who offroad still drive mostly on paved roads getting there or being at home for daily or weekly use.

Off road, when going over undulated terrain it allows for independent, actuator displacement, more specific opposite wheels to go up and down aka articulation, without the need for any part of the system to be controlled

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What does this mean?
- When you work on the suspension and do not want the actuators to work against you, opening the allen or hex bolts allows coms beteen the yellow and green circuits. This is advisable anyways to prevent immediate lean issues when you are done. I had this happen taking off wheels one by one with a jack instead of the dealer car lift for rotation, without opening the KDSS bolts the 1.5 to max 2 turns.
- Once you are done with suspension work and before closing the bolts to separate yellow from green, make sure the vehicle is level and then close the bolts. I have experienced first hand to do this wrong, had a lean, then opened the bolts again on a flat surface, rock the car a bit standing on the running boards or rock sliders holding the roof rack, then wait a few minute, check all is level without lean and close the KDSS bolts. This is enough to resolve a lean vs using some shims and forcing it, unless the suspension is not balanced in which case that is a temporary fix.
- IN CASE OF LEAN, the issue/root cause is not KDSS. It is the suspension setup and or springs not supporting the frame and body such it is level. In case that is not correctly balanced (I understand passenger fuel side is a little more stiff than driver side on factory setup) the KDSS over time due to a slow leak past the actuator will adjust to that position. As a result anybody parking their LC200 on an inclined driveway (sideways, this is very unusual minus the odd exception as was discussed somewhere else on this forum) will experience lean as KDSS will over longer time balance fluid across its internal actuator piston seals from yellow to green or the other way.
- This also means that those who have forced their lean to go away using KDSS are putting the system under constant additional pressure, which depending on the amount will probably shorten seal live. Consider in a balanced setup with level suspension and KDSS bolts closed with the vehicle level there is no delta pressure across the actuator seals separating yellow from green. There is ofcourse pressure to any seal to ambient at the 400 psi or so operating pressure of the system. Those seals maybe more robust in design or have a primary and back up.

So all in all as per linuxgod and bloc and probably others, the focus should be on leveling the vehicle with spring shims or move around springs or buying new once (sigh...) and then check it has a level stance with the KDSS bolts undone 1.5 to max 2 turns.

Hope this helps. Also happy to be challenged if I got this wrong.
 
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The driver side is lower of 1"
Use trim packers on the drivers side.

You can try to swap the springs and put the longer spring on the drivers side, but you’ll likely end up with a lean the other way and will need trim packers (possibly more of them) on the passengers side. It’s much easier to install them on the drivers side as the spring will basically fall out once you unbolt the shock and jack that side up.

Btw lean height is affected by weight and I think sometimes the manufacturers make assumptions about how much extra weight you’ll be carrying depending on spring stiffness
 
I developed a lean with my Ironman springs too. 1.25" low on the driver side (yes, the springs are in their correct locations). Added a trim packer from Kurt to get close to level.
I've subsequently decided that I hate the ride enough to just replace the springs (and maybe shocks). I previously had Ironman FCP medium all around and was happy with the ride but they settled over the course of about 70k miles and I wanted to get ride height back. I went to their medium-plus kit with nitro shocks and now the ride is harsh, so I feel every expansion joint and ripple in the pavement.
Does anyone make a more progressive setup that allows for compliance over small bumps without turning into a marshmallow-like ride?
 
I developed a lean with my Ironman springs too. 1.25" low on the driver side (yes, the springs are in their correct locations). Added a trim packer from Kurt to get close to level.
I've subsequently decided that I hate the ride enough to just replace the springs (and maybe shocks). I previously had Ironman FCP medium all around and was happy with the ride but they settled over the course of about 70k miles and I wanted to get ride height back. I went to their medium-plus kit with nitro shocks and now the ride is harsh, so I feel every expansion joint and ripple in the pavement.
Does anyone make a more progressive setup that allows for compliance over small bumps without turning into a marshmallow-like ride?
I currently have the exact situation and it’s being rectified as we speak and I also had a 1.25 drop on the drivers side. I have the Ironman FCP from previous owner install. The shop apparently put the front shock on the wrong side. It come with a left and a right. My current awesome shop discovered this and also the fact they got air into the kdss probably from turning past three turns. So it’s being rectified-pressurized and putting 6112 Bilsteins full kit with 2722 springs in the rear.
 
Hoping to resurrect some aspects of this thread. I had the local Toyota dealer install the leveling kit in front on my 2013 LC. At the same time as leveling kit install I had them put on slightly larger than stock KO3s. During the process, they had all kinds of issues with rust on the accumulator valves and also with rusted out lines - all had to be replaced which was $$$. Since then, the lean has been noticeable. Not sure if it was there before, though. My fault for not looking. SINCE SINCE THEN, however, my 2013 also rolls pretty badly from side to side. Like the KDSS isn't really doing its job. Feels unsafe with just me in the car and very unsafe when I have a full load of people and bags. Is this a KDSS bleed issue? The vehicle only has 128K on the odometer so I don't think the springs are the problem. Any insight on this? I may also ask the FB 200 group. Thanks.
 
Hoping to resurrect some aspects of this thread. I had the local Toyota dealer install the leveling kit in front on my 2013 LC. At the same time as leveling kit install I had them put on slightly larger than stock KO3s. During the process, they had all kinds of issues with rust on the accumulator valves and also with rusted out lines - all had to be replaced which was $$$. Since then, the lean has been noticeable. Not sure if it was there before, though. My fault for not looking. SINCE SINCE THEN, however, my 2013 also rolls pretty badly from side to side. Like the KDSS isn't really doing its job. Feels unsafe with just me in the car and very unsafe when I have a full load of people and bags. Is this a KDSS bleed issue? The vehicle only has 128K on the odometer so I don't think the springs are the problem. Any insight on this? I may also ask the FB 200 group. Thanks.
If they didn't bleed the system correctly, which is possible as very few dealers ever mess with these systems, it would absolutely lead to excess roll in corners.

I'd try to get it back in there and have them verify the system pressure.
 
If the dealer is not familiar with the pressurizing procedure, that can easily have been done wrong. I had a difficult time finding a qualified dealer here in Boston to work on my 4Runner, with the same KDSS system.

It may be that the valves weren't opened, after pressurized, while the suspension work was performed. This must be done to allow equilibrium in the system. Although one can bleed and pressurize the system only through the bleed nipple, dealers will follow the service manual and bleed each stabilizer valve. As noted above, this could have been done in error.

FYI, I purchased an accumulator for about $550, a front stabilizer (shock) for the same, from two sources in Japan. Although it took about a month to ge them, it was well worth it.

My dealer installed these and front lines for $800. Reasonable. The truck is level, even after a complete suspension swap.

Finally, you should spray the accumulator and everything else with PB Blaster Surface Shield, Fluid Film or similar to prevent further corrosion. I use the PB Blaster. Annual inspections by removing the cover is also a must.
 
Coat the bottom where the two screws are with marine grease. I do this every year and even after 8 years of Chicago winters mine still look good and turn without issue.
 

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