JKS disco (for 2.5-6 inch lift) measurement needed

matkal

matkal

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I have a set of (0-2”)JKS discos on my TJ that I’m in the process of lifting 3”. I want to add the appropriate length to the set I have rather than by new ones.
If you have the 2.5-6” JKS discos, could you please provide the measurement described in the pic? TIA
8AEDA954-2536-43C2-BFD2-08E363335D9B.jpeg
 
It's hard to measure exactly on the LJ, but it's 5-3/4" ± 1/8".
 
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If I'm not mistaken, Sway Bar Links don't have a static "length" to be set to.
Sway Bar Link measurements will vary depending on a number of factors. (Every 4" lift kit isn't exactly 4")

Sway bar disconnects should be installed at normal ride height, on flat level ground.
The "optimal sway bar angle" according to JKS is 10 degrees on the TJ platform.

With links OFF, hold your sway bar so the arm position is at roughly 10 degrees.
Then adjust & install your sway bar disconnects to their respective mounting locations without inducing preload/tension on the sway bar.

The swaybar should not have tension applied while on flat ground, only during axle articulation.

You'll need to lengthen them enough to hold the sway-bar at that angle.
Any significant amount more or less is going to cause issues.

So technically you could remove the sway bar end links, hold the sway bar at 10 degrees, and measure how long you'd need to lengthen them.
Taking measurements from another TJ, with a different suspension setup, isn't going to get you perfectly where you need to be.
 
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Matkal has the shorter arms. They aren't long enough for the sway bar to be at roughly 10° at ride height with additional lift. He's inquiring because he's going to lengthen them, rather than buy the longer version. It's not simply a matter of adjustment. It's a matter of wrong parts...
 
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sab said:
Matkal has the shorter arms. They aren't long enough for the sway bar to be at roughly 10° at ride height with additional lift. He's inquiring because he's going to lengthen them, rather than buy the longer version. It's not simply a matter of adjustment. It's a matter of wrong parts...
Click to expand...

This is also true, and I misread the original intentions of trying to re-use the wrong parts.
 
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zachpeakee said:
I doubt you'll pull the length needed out of the short links you currently have, without inducing preload on the swaybar. @matkal
Click to expand...

The links being short has nothing to do with preload. As long as the links are the same length at ride height, there is no preload - even if they are too long or too short. The problem with links being too long or too short is that they can go over-center or they can limit travel. He's planning to lengthen them, which will be successful if done right. It ain't rocket science.
 
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sab said:
The links being short has nothing to do with preload. As long as the links are the same length at ride height, there is no preload - even if they are too long or too short. The problem with links being too long or too short is that they can go over-center or they can limit travel. He's planning to lengthen them, which will be successful if done right. It ain't rocket science.
Click to expand...

You're right.
I wasn't thinking with my brain, and worded that last comment incorrectly.

It's been a long day!
 
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sab said:
Matkal has the shorter arms. They aren't long enough for the sway bar to be at roughly 10° at ride height with additional lift. He's inquiring because he's going to lengthen them, rather than buy the longer version. It's not simply a matter of adjustment. It's a matter of wrong parts...
Click to expand...

It is still useful to hold the bar at 10* as a starting point though.then you measure what you want the links to be and go modify.no need to ask for measurements anymore. You guys are both right.
 
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zachpeakee said:
If I'm not mistaken, Sway Bar Links don't have a static "length" to be set to.
Sway Bar Link measurements will vary depending on a number of factors. (Every 4" lift kit isn't exactly 4")

Sway bar disconnects should be installed at normal ride height, on flat level ground.
The "optimal sway bar angle" according to JKS is 10 degrees on the TJ platform.

With links OFF, hold your sway bar so the arm position is at roughly 10 degrees.
Then adjust & install your sway bar disconnects to their respective mounting locations without inducing preload/tension on the sway bar.

The swaybar should not have tension applied while on flat ground, only during axle articulation.

You'll need to lengthen them enough to hold the sway-bar at that angle.
Any significant amount more or less is going to cause issues.

So technically you could remove the sway bar end links, hold the sway bar at 10 degrees, and measure how long you'd need to lengthen them.
Taking measurements from another TJ, with a different suspension setup, isn't going to get you perfectly where you need to be.
Click to expand...

Don't get bogged down by numbers. The sway bar should be roughly parallel to the frame at the mid-point of the shock travel.

After that, confirm that the sway bar cannot flip over at full shock extension. Do this by hanging the axle from the shocks. The sway bar and links should have a bend at the joint and should not be pulled tight.
 
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