Icon Stage 10 EKDSS issue with OT (1 Viewer)

[ESdoc550]

I posted on ih8mud but no bites. I have a GX550 OT and I'm in the process of installing ICON Stage 10 suspension. As some of you may know, ICON doesn't officially support this kit for the OT trim. I spoke with an ICON rep at the Overland Expo last month to find out why, and the explanation was more interesting than I expected.

Installing the Stage 10 kit increases suspension droop and as a result the downward travel at the rear axle is physically limited by the EKDSS. The added droop requires roughly 1/4" more travel than the EKDSS is designed to allow, which translates to about 3/4" to 1" at the wheel. It's not something you'd notice while driving, which is probably why it hasn't come up much. But the concern is that over time, the EKDSS components end up absorbing force they weren't designed to handle when limiting that downward travel, potentially leading to premature wear or failure.

I was surprised because I'd never seen this discussed anywhere. Most forum threads either focus on AVS error codes after a lift, or people saying everything is fine. I'm hoping someone here can either confirm this explanation or share whether they've run into it. More importantly, has anyone found a solution? Rep mentioned that putting shims inside the shock would limit downward travel but that seems to defeat the purpose. Maybe a modified bracket, a different approach, anything? Would love to hear from anyone who's dug into this.

 

[BoostedGX]

I posted on ih8mud but no bites. I have a GX550 OT and I'm in the process of installing ICON Stage 10 suspension. As some of you may know, ICON doesn't officially support this kit for the OT trim. I spoke with an ICON rep at the Overland Expo last month to find out why, and the explanation was more interesting than I expected.

Installing the Stage 10 kit increases suspension droop and as a result the downward travel at the rear axle is physically limited by the EKDSS. The added droop requires roughly 1/4" more travel than the EKDSS is designed to allow, which translates to about 3/4" to 1" at the wheel. It's not something you'd notice while driving, which is probably why it hasn't come up much. But the concern is that over time, the EKDSS components end up absorbing force they weren't designed to handle when limiting that downward travel, potentially leading to premature wear or failure.

I was surprised because I'd never seen this discussed anywhere. Most forum threads either focus on AVS error codes after a lift, or people saying everything is fine. I'm hoping someone here can either confirm this explanation or share whether they've run into it. More importantly, has anyone found a solution? Rep mentioned that putting shims inside the shock would limit downward travel but that seems to defeat the purpose. Maybe a modified bracket, a different approach, anything? Would love to hear from anyone who's dug into this.

I think it’s a rare case since not many are able to get the suspension to that full droop point . But maybe you plan to

 

[Bluegill]

Can limiting straps be used?

 

[ESdoc550]

Can limiting straps be used?

That may be a solution to limit downward travel similar to adding shims inside a shock to protect the ekdss. I'm hoping for a solution that resolves ekdss binding without limiting travel of suspension. I think there are similar solutions to the older non electronic kdss models.

 

[DJ’s Sled]

So..the downward travel limitation from the EKDSS you guys are discussing is still a factor, still at play even when the rear EKDSS has disconnected itself? Apologies for a less than perfect understanding. TIA.

 

[MinnowGT]

maybe the drkdss trackbar relocation will help with some of the extended travel pull. KDSS Upgrades for Land Cruiser 250 & GX550 | DrKDSS. I think you might be able to ask them on other ideas as they have a bit of experience with this.

 

[ESdoc550]

So..the downward travel limitation from the EKDSS you guys are discussing is still a factor, still at play even when the rear EKDSS has disconnected itself? Apologies for a less than perfect understanding. TIA.

Yes, but I dont understand the exact mechanics yet. I would have to lift truck and flex the suspension which I'm unable to do. I thinknit does "fully disconnect". It has a range it works in which is sufficient with stock suspension but not the Stage 10 kit.

 

[ESdoc550]

maybe the drkdss trackbar relocation will help with some of the extended travel pull. KDSS Upgrades for Land Cruiser 250 & GX550 | DrKDSS. I think you might be able to ask them on other ideas as they have a bit of experience with this.

Yes, my shop is planning to reach out to DrKDSS

 

[willboy]

I’ve seen several builds with stage 10 by Dissent Off-road, so I assume they must have figured out a fix. You might reach out to them and ask about their experience. They wheel their rigs hard.

 

[cmfhsu]

Yes, but I dont understand the exact mechanics yet. I would have to lift truck and flex the suspension which I'm unable to do. I thinknit does "fully disconnect". It has a range it works in which is sufficient with stock suspension but not the Stage 10 kit.

Here's a great video explaining the technical and suspension mechanics of how EKDSS works:

I suspect the problem you're going to run into isn't the extra droop, but the extra suspension articulation you get. Foundationally, EKDSS is still a normal sway bar, so you can have basically as much droop as you want without the sway bar having any effect - as long as both wheels are drooped (like on a jump). But I bet you the extra articulation allows one rear shock to drop lower than standard, which would let the entire weight of the rear suspension (or possibly the entire car) transfer into the EKDSS actuator, which is stress it's not designed to handle.

Really not sure how you'd solve this one. Using limiting straps would fix the problem, but then you're losing the extra suspension articulation you paid for. You could redesign the EKDSS linkage so it has a lower motion ratio, but I'm not sure if the electronic control is programmed specifically for the expected linkage. In the old hydraulic-only days, that might have been reasonable because it was only on / off, but I'm not sure if the electronic system works in fancier ways.

When you get into hardcore, heavily modded suspension, you might have to simply forgo your rear sway bar or switch to a regular, non-EKDSS sway bar until somebody clever solves it.

 

[ESdoc550]

Here's a great video explaining the technical and suspension mechanics of how EKDSS works:

I suspect the problem you're going to run into isn't the extra droop, but the extra suspension articulation you get. Foundationally, EKDSS is still a normal sway bar, so you can have basically as much droop as you want without the sway bar having any effect - as long as both wheels are drooped (like on a jump). But I bet you the extra articulation allows one rear shock to drop lower than standard, which would let the entire weight of the rear suspension (or possibly the entire car) transfer into the EKDSS actuator, which is stress it's not designed to handle.

Really not sure how you'd solve this one. Using limiting straps would fix the problem, but then you're losing the extra suspension articulation you paid for. You could redesign the EKDSS linkage so it has a lower motion ratio, but I'm not sure if the electronic control is programmed specifically for the expected linkage. In the old hydraulic-only days, that might have been reasonable because it was only on / off, but I'm not sure if the electronic system works in fancier ways.

When you get into hardcore, heavily modded suspension, you might have to simply forgo your rear sway bar or switch to a regular, non-EKDSS sway bar until somebody clever solves it.

Thank you, I'll review the videos. I'll share if my shop figures anything out

 

[ESdoc550]

maybe the drkdss trackbar relocation will help with some of the extended travel pull. KDSS Upgrades for Land Cruiser 250 & GX550 | DrKDSS. I think you might be able to ask them on other ideas as they have a bit of experience with this.

I think correcting the track bar is a different issue. Returns rear axle to a linear portion of motion preventing left right sway