How does a sway bar disconnect help off-road?
We know that a sway bar is there to help reduce body roll, so, why would you want to disconnect a sway bar?
Updated January 28 2021
Being able to disconnect a vehicle’s sway bar(s) will be nothing new to four-wheel drivers but for, say, a Mustang owner, the idea of disconnecting their vehicle’s sway bar(s) would be madness. So, let’s start at the beginning with a description from ‘Explaining what a sway bar is’. We’ll work back from there.
What is a sway bar?
A sway bar connects your vehicle’s suspension components (one side of the vehicle to the other) and is mounted to the suspension control arms. It’s worth noting that sway bars run through bushings to ensure they don’t move up and down and can only twist in response to action on one wheel or the other. A sway bar works by resisting the twisting force applied to it when one wheel moves down or up compared with the other wheel and weight transfers from one side of the vehicle to the other – when you’re turning a corner, for instance. And, in that resistance, the bar tries to keep the wheels as level as possible.
So, as the vehicle turns a corner and weight moves from one side to the other (in the case of a right-hand turn the vehicle rolls over to the right. As the wheel begins to move up towards the body, the sway bar twists which forces the weight to transfer back across to the other side of the vehicle. The result of this action is that the vehicle begins to level out, thus minimising the roll action when cornering.
The point of a sway bar is that it improves your vehicle’s on-road, at-speed, performance by reducing bodyroll and thus improving grip and control. Depending on how stiff or soft the sway bar is in your vehicle you can dial in or out either under or oversteer. Sway bars are incredibly important bits of your vehicle.
Why disconnect your vehicle’s sway bars?
We need to point out here that this relates to four-wheel drives only. There’s no reason at all why you’d want to disconnect the sway bars on your road car. And, for a four-wheel drive you only want to disconnect them when driving at low speeds off-road.
Sway bars are designed to ensure your vehicle’s wheels don’t move too far up or down independently of the opposite wheel. But when you’re off-road and negotiating rough terrain, you want your 4×4’s wheels to be able to travel as far as possible independently of the other side to maintain contact with the ground and that’s what being able to disconnect the sway bar means.
How does a sway bar disconnect work?
While sway bar disconnects are available for a range of 4x4s as aftermarket options, the best-known factory sway bar disconnect is the Jeep Wrangler Rubicon. This is an electric sway bar disconnect and is activated via a button inside the vehicle. It operates on the front sway bar and can only be disconnected in either 4-high or 4-low.
Once you press the button to disconnect the sway bar the light on the dashboard will blink. This tells you the electric motor is, via some mechanical jiggery pokery separating the two sway bars. Once the light is solid you’re good to go. And, as you can see in the image below which shows the old model Wrangler Rubicon, disconnecting the sway bar can give you a lot more wheel travel then when it’s engaged as it would be for road driving.