KDSS Suspension Tech
January 21, 2020
What is KDSS and what does it do?
KDSS stands for Kinetic Dynamic Suspension System and it uses hydraulic rams attached to a very stiff sway bar in order to control body roll and articulation. The main purpose of the system is to improve on-road handling and to reduce body roll. Off-road the system is advertised to increase articulation and stability. The design of the system can have some drawbacks when lifting your 4runner. Read more below on how to overcome these obstacles in order to get your 4Runner looking better and riding better.
How does the KDSS system work?
The KDSS system has a hydraulic ram connected to the passenger side of the sway bar and a fixed link on the driver side. The sway bar is extremely stiff and the hydraulic ram extends or compresses to control the body roll and articulation.
Year models it comes on? (optional)
2010+ Toyota 4Runner TRD Offroad
2008+ Toyota Land Cruiser
2004+ Lexus GX
2010+ Toyota Prado
Can you lift 4Runners with KDSS?
KDSS equipped 4Runners can be lifted, however there are two common issues: KDSS lean and poor ride quality.
Based on the limitations of the KDSS system we recommend lifting KDSS equipped 4Runners a maximum of 2.5” in front and 1” in rear. With this setup we have not had problems with leaning and the ride quality is fantastic.
What causes KDSS lean?
KDSS lean is the most common issue to occur if you lift your 4Runner too high. The electronics and hydraulics don’t like too much lift and the system will cause the 4Runner to lean to the driver side. The only solution we have found is simply not to lift them too high.
What are the travel limits in the rear?
Rear suspension travel on KDSS 4runners is limited primarily on the passenger side. In some circumstances the stiff sway bar and fixed mounting point will reach their limit and bind up. In other situations the panhard bar will hit the axle. We have not seen a rear panhard bar that offers a substantial amount of additional rear travel.
KDSS 4Runners can use stock travel or extended travel rear shocks. Extended travel shocks will allow for more articulation on the driver side rear but will let the panhard to hit the axle in droop on the passenger side. The longest shock that will fit without contact is 25” from the upper shock mount to the center of the lower shock bolt. Plenty of KDSS equipped 4Runners have shocks measuring 26” or more without issue, they just don’t use the full shock travel.
KDSS Drop Bracket
Black Gate Customs offers a KDSS drop bracket designed to keep the track bar from contacting the sway bar when the suspension is at full droop. This drop bracket can help with adding more lift height, however it does push the sway bar out more and may get hit by rocks when off-road. More info about these brackets can be found here.
Can you disconnect the KDSS system?
We do not recommend disconnecting the system as it may cause check engine lights or void the warranty. The system is both electronic and hydraulic and should be maintained by the dealer.
Summary:
The KDSS system can be beneficial to on-road handling but has some restrictions on lift height and rear suspension travel. If you want to lift your 4Runner more than 2.5” in front and 1” in the rear you should consider getting a non-KDSS equipped 4Runner.
