RTH need front KDSS valve/shock measurement please

[silverhorse]

Guys, on the front kdss valve/shock... I need a measurement of the area that's covered by the accordion style boot. At the top and bottom of the boot is a stainless steel clamp. If you can measure from the top clamp to the bottom clamp that would be awesome thank you very much!

 

[silverhorse]

FYI, the measurement needs to be taken at ride height , truck sitting level. Please note if you have any lift or stock. Thanks

 

[Yossarian]

Does this help?

 

[silverhorse]

@Yossarian thank you. Yes... is your suspension stock or lifted? TY

 

[Yossarian]

Slight lift. Bilstein 4600 shocks, adjustable spring perch, middle position, with OEM spacer above strut.

That said, the 13 year old springs are sagging.

 

[silverhorse]

Awesome good info. I'm trying to establish where most folks neutral position for the kdss valve is.... so I can come up with a length for my sway bar links...
I'm going to lengthen my sway bar links because I have approximately 3 to 3.5 inch of lift ...

looks like yours is somewhere between 4 and 3/4 to 5 in

 

[nwfl4runner]

Is there any concern about the sway bar at full bump using longer links?

 

[silverhorse]

@nwfl4runner that is a good question! I guess what I need to do is measure the distance between ride height and fully extended on the lower A-Arms to establish my shock extension...
I was thinking the kdss valve should be at stock position(neutral) or close.. at ride height. But maybe not?

 

[nwfl4runner]

I wish I knew more about how the KDSS works! I just think extending those links might introduce a new problem. You tried welding on the valves?

 

[bloc]

Here’s the thing.. even with a lift, my understanding is the KDSS cylinder lengths should remain the same. The only time they “should” lengthen or compress is when you are articulating. One exception to this would be if you have a lean one direction or the other.

 

[silverhorse]

@nwfl4runner yep still no luck getting the valves open. But maybe I will try again.

@bloc that's what I'm thinking as well. That's why I want to find out what the length of the kdss valve is in the neutral or ride height position so I can plan accordingly..

 

[silverhorse]

Once I get the kdss valve into the neutral position then I can measure from the sway bar mount hole on the sway bar to the sway bar link hole on the lower A arm to establish the sway bar links length...

 

[CharlieS]

2016 with King suspension and approx. 2.5" lift

 

[silverhorse]

Thank you for the input @CharlieS !
I'm going to assume that's about 5 inches to 5 and 1/4 inches?

 

[bloc]

Once I get the kdss valve into the neutral position then I can measure from the sway bar mount hole on the sway bar to the sway bar link hole on the lower A arm to establish the sway bar links length...

I suspect you might be going about this the wrong way. As I mentioned the end of the cylinder acts as the left sway bar pivot. Think of it as a method to tilt the sway bar either way, in fact in 4runners the KDSS cylinders do just that, they tilt the whole thing. On our rigs we get better ground clearance by having the bar itself up against the frame and the left pivot moving up and down in space.

As long as your front suspension is even side to side, and your sway bar links are the same length (or however offset the stock ones are, for whatever reason they did that), the cylinder length should stay static.

Meaning even if both links got really long, cylinder length should be the same as if they were really short. Or the suspension set very high, same as very low.

Likewise, I think you might find some variation in the cylinder length of different vehicles, not necessarily because of lift, but possibly different cruiser leans and potentially sway bar input to combat it. That is a primary reason toyota designed in the ability to balance the system with the balance screws.. yes different heights and weights and variations from rig to rig, but open the valves, let it all settle wherever the cylinders want, then lock in that setting by closing the screws.

If you are attempting to extend the links, just do so the same length on both, and don’t worry about the cylinder length.. whatever you need to do to compress it and get the link in will still need to happen.



Apologies if my attempt to explain this just confuse things further. This is a complex system and I’ve spent a lot of time trying to understand it, but I’m not sure my ability to explain it has caught up.

 

[silverhorse]

Thank you @bloc your input is much appreciated! I'm just concerned since my kdss is not hooked up that the cylinders have extended all the way out..
That is why I'm trying to compress it and establish a reasonable link length.
And FYI I have still not been able to unfreeze my kdss valves

 

[bloc]

Thank you @bloc your input is much appreciated! I'm just concerned since my kdss is not hooked up that the cylinders have extended all the way out..
That is why I'm trying to compress it and establish a reasonable link length.
And FYI I have still not been able to unfreeze my kdss valves

Per my understanding from tearing down the KDSS valve it can try to extend the cylinders when they aren't retained by the arm, there is a flow path from the accumulators into both circuits of the cylinders, and there is more surface area in the upper part of the cylinder than the lower so on balance they will try to extend. You also should be able to push them back in, but that requires overcoming a "pop-off" valve effect within the KDSS valve.

See post 6, and the third picture in post 10 of this thread: Anatomy of a KDSS valve - https://forum.ih8mud.com/threads/anatomy-of-a-kdss-valve.1230554/