KDSS "tuning" for 2019 model year?

[campgaw]

Hello,

This is my second 200. The first was a 2016. A tree fell on it.

My new 200 is a 2019. I swear the older truck performed better on the road. The new truck has more body-roll.

Is it possible that the KDSS needs to be stiffened? Is it possible to tune the system by adding or removing oil from the lines?

If yes, is there any chance this is something that Toyota can do at one of their dealerships?

Any insight greatly appreciated, thanks.

 

[turbo8]

What kind of tires and tire pressure did each LC have? Any mods done to the 2016?

 

[campgaw]

What kind of tires and tire pressure did each LC have? Any mods done to the 2016?

Both were/are bone stock. Tire pressure might be a little high on the 2019 because the last time I adjusted PSI was in the winter. But we're talking +/- 5 PSI.

 

[stiffarm]

My 2021 LC sits higher than my former 2015 and the steering is decidedly more difficult to turn---more preload. I like the 8 speed tranny.


lC

 

[campgaw]

My 2021 LC sits higher than my former 2015 and the steering is decidedly more difficult to turn---more preload. I like the 8 speed tranny.


lC

Yes, I also noticed that the steering is stiffer on the 2019 as well.

 

[bloc]

To my knowledge there is nothing that can be tuned on the KDSS. It is possible that something having leaked would allow more body roll but other than the high pressure accumulators (which are very robust) the entire system is full of oil. If you had a leak there would be evidence of it somewhere.

To verify pressure level within the system you’ll need to find a dealer that has the specialized tool for working on KDSS. My understanding is said tool is pretty rare, with most regions only having a handful, and the dealers shipping them around as needed.

One thing you can check is whether the balance valves were inadvertently left open. This would effectively disconnect your sway bars. If you want to try and do this let me know.. it isn’t too hard to find but you’ll want to be sure you don’t over torque the bolts, and they have a pretty low spec.

 

[campgaw]

To my knowledge there is nothing that can be tuned on the KDSS. It is possible that something having leaked would allow more body roll but other than the high pressure accumulators (which are very robust) the entire system is full of oil. If you had a leak there would be evidence of it somewhere.

To verify pressure level within the system you’ll need to find a dealer that has the specialized tool for working on KDSS. My understanding is said tool is pretty rare, with most regions only having a handful, and the dealers shipping them around as needed.

One thing you can check is whether the balance valves were inadvertently left open. This would effectively disconnect your sway bars. If you want to try and do this let me know.. it isn’t too hard to find but you’ll want to be sure you don’t over torque the bolts, and they have a pretty low spec.

Thanks for the useful reply.

If the sway bars were effectively disconnected I suspect the body roll would be more pronounced. I think it would be worth checking the valves anyway, though. Is it possible that they could be partially open, only partially affecting roll?

Also, stiffarm mentioned that his 2021 sits higher than his 2015 - if this is the case with the 2019 as well, it sounds like something that could affect body roll?

 

[bloc]

Thanks for the useful reply.

If the sway bars were effectively disconnected I suspect the body roll would be more pronounced. I think it would be worth checking the valves anyway, though. Is it possible that they could be partially open, only partially affecting roll?

Also, stiffarm mentioned that his 2021 sits higher than his 2015 - if this is the case with the 2019 as well, it sounds like something that could affect body roll?

Unless the 21 is a heritage it shouldn’t be any taller, they even use the same part number for one of the springs in the back. Totally possible the 15 had sagged springs though.

The two balance screws each open one (upper or lower) cylinder circuit to the central balance circuit.. maybe if one were open and one closed it would be less roll, but not dramatic. To be honest I’m not sure. The way the screws work they don’t need to be very tight to do their job.. factory spec is only 9ft-lb, which is very very easy to go past with a basic hand tool.

Getting under there to check is very easy.. tons of stuff on KDSS in this section, but basically get under the truck at the drivers side rear door. Inside of that frame rail is a thin metal cover with two oval holes in the bottom. On a 2018 or later lined up with those holes you will see two small 8mm head bolts (5mm internal allen for 08-17), just see if they are snug. If they are backed out at all the circuits are open and could explain your observations. DO NOT LOOSEN THEM MORE THAN THREE TURNS if you feel the need to see if they are tight by loosening. No risk to go less than that, but more, and you will have big expensive problems.

 

[campgaw]

Unless the 21 is a heritage it shouldn’t be any taller, they even use the same part number for one of the springs in the back. Totally possible the 15 had sagged springs though.

The two balance screws each open one (upper or lower) cylinder circuit to the central balance circuit.. maybe if one were open and one closed it would be less roll, but not dramatic. To be honest I’m not sure. The way the screws work they don’t need to be very tight to do their job.. factory spec is only 9ft-lb, which is very very easy to go past with a basic hand tool.

Getting under there to check is very easy.. tons of stuff on KDSS in this section, but basically get under the truck at the drivers side rear door. Inside of that frame rail is a thin metal cover with two oval holes in the bottom. On a 2018 or later lined up with those holes you will see two small 8mm head bolts (5mm internal allen for 08-17), just see if they are snug. If they are backed out at all the circuits are open and could explain your observations. DO NOT LOOSEN THEM MORE THAN THREE TURNS if you feel the need to see if they are tight by loosening. No risk to go less than that, but more, and you will have big expensive problems.

Excellent, thanks for the advice. I'll check it out. Again, very much appreciated.