Treaty Oak Offroad KDSS Spacers Overview for the 5th Gen 4runner

There is a clear difference in road manners when driving a KDSS-equipped 4Runner versus a non-KDSS model. But after lifting a KDSS-equipped vehicle, one can encounter a lean towards the passenger side, which looks terrible and affects the ride quality.

So, I had to address the issue after I lifted my 2021 4Runner, and my research led me to Treaty Oak Offroad KDSS spacers.

Find It Online

• KDSS Spacer Kit: Check price
• Updated Product Line (Fixed Link Spacer & Original Spacers: Check Prices

Initial Impressions

The quality and finish of the product are very good. The kit comes with 3 KDSS spacers (1 for the front passenger side and 2 for the rear passenger and rear driver sides). It’s made of 6061 aluminum, type 3 hard-coated anodized in black, and comes with new hardware.

In my opinion, the kit is priced extremely well for the value it provides, and it looks very stock to a normal eye.

What is KDSS and KDSS lean?

A little bit about KDSS first.

KDSS stands for Kinetic Dynamic Suspension System, a technology borrowed from the Lexus GX and Land Cruiser series. It optimally adjusts the front and rear stabilizers using a set of interconnected hydraulic cylinders. The interconnection consists of hydraulic piping and a control cylinder located on the frame rail. KDSS, which is fully mechanical, can disengage the stabilizer bars (the bars are jointed, allowing independent movement). This system will not engage during normal driving conditions when the hydraulic pressure is equal. In off-road conditions, KDSS activates when it senses that a wheel has dropped.

One of the problems with this KDSS system is “the lean”. KDSS lean is where the passenger side sits a little lower than the driver side, thereby generating a lean, and this is developed after you lift your vehicle. The reason for this is that when your vehicle is lifted, the cylinder extends as the vehicle is raised, but the passenger side can’t due to the rigid link.

Why do you need KDSS Spacers?

There are a few things that can be done to get rid of this lean. A cheap alternative would be to add a strut-top spacer plate to the passenger front and rear, and taller coil springs on the passenger side, to offset the lean. At the time of this post, only Dobinsons offers different-length coil springs for the rear of KDSS-equipped trucks if you plan to go this route.

The other option will be KDSS spacers, which extend the length of the passenger front bar by adding a spacer in there and adding 2 spacers in the back on both sides. The latter option will not only correct lean but also add some droop to the suspension travel, increasing articulation while off-roading.

TREATY OAK OFFROAD or  BLACK GATE CUSTOMS?

There are 2 options for KDSS spacers out there—Treaty Oak Offroad and Black Gate Customs, which were previously covered on Trail4Runner. The product’s creator can now be found on Instagram and goes by the handle @Dr_KDSS. He does not claim to be the KDSS doctor, though; his initials are simply DR. That said, DR. KDSS applies because he fixed major issues with KDSS. He also manufactures the KDSS on/off switch. As the name implies, it allows you to turn KDSS on/off with the push of a button.

Both Black Gate Customs and Treaty Oak Offroad achieve the same thing in the rear, but Black Gate Customs does not offer a spacer for the front, which is strange.

Because of this, I went with the Treaty Oak Offroad kit.

Install Overview

The kit includes 3 spacers and some bolts.

(Use hand tools only for this install)

Start by parking the vehicle on level ground to normalize pressure in the DSS hydraulics. Now, remove the front skid plate to give yourself more clearance for installing the front KDSS spacer.

Treaty Oak’s instructions mention loosening KDSS shutter valves 2 turns, which are located on the driver side (Don’t forget to remove the top cover first), but I did not want to mess with the system, so I skipped this part and had no issues. In that link, you will find some documentation on how to loosen the KDSS accumulator assembly.

FRONT:

Place a floor jack under the sway bar under the driver-side link. Jack up the sway bar to apply a little pressure to it. Now, carefully loosen and remove the bolts on the passenger side fixed link.

Lower the jack slowly until there is room to install the spacer on the link side. Jack the sway bar back up to get the sway bar/bushing to sit in the spacer. Next, install the collar on the bottom of the sway bar, and start both bolts by hand. Lastly, tighten the bolts (alternate back and forth) to 30 ft/lbs, then remove the floor jack.

REAR:

Move the floor jack to the rear sway bar, just to the right of the cylinder. Jack up and put pressure on the sway bar, loosen the bolts, and remove it. Now, lower the way bar and install the driver-side spacer. Jack the sway bar back up, install the collar, and tighten the new bolts in alternating passes to 52 ft/lbs.

Next, move to the passenger side, jack up the sway bar just to the left of the cylinder, and remove the bolts. Lower the jack/sway bar and install a spacer between the link and the sway bar. Jack up and position the sway bar inside the spacer, then install the collar and tighten the new bolts to 52 ft/lbs, just like you did with the front. Finally, rock the vehicle side to side and allow it to settle.

Final Thoughts

Adding these spacers will equalize pressure in the KDSS system and return the sway bar angle to OEM specifications after a lift is installed. In turn, this will dramatically reduce or eliminate your lean. This will help with ride quality, as you’re correcting the geometry after lifting your vehicle, and will also improve articulation while off-roading.