What Is a Sway Bar and What Type Is Best for Your Vehicle?Last Updated February 9, 2024 | Meghan Drummond
Sway bars prevent body roll and offer stability for your vehicle. That’s why you’ll also hear them referred to as “anti-roll bars” or “stabilizer bars.”
Sway bars make it easier to carve corners or make tight turns without losing control. Though you usually won’t notice your sway bars, you’ll appreciate them the next time you need to make a U-turn. Many vehicles, including the Ford Mustang and Jeep Wrangler, come with stock sway bars in the front and rear. But many drivers upgrade to an aftermarket sway bar to improve their performance.
How Do Sway Bars Work?
Sway bars are torsion springs, just like the ones you’ll find in clothes pins or clipboards. By resisting rotation, they help return things to their original position. A clipboard that opens but doesn’t immediately snap closed would be pretty useless. On your car, the sway bar returns your wheels to the same height and keeps your vehicle level.
The sway bar runs parallel to the axle and attaches to the control arms on both sides. They’re also attached to the frame. This links the two sides of your suspension together.
For one wheel to be higher than the other, the sway bar has to twist. The sway bar resists that twisting and returns the wheels to the same height to level out your ride. That’s why sway bars don’t even out bumps (when both wheels raise and lower at the same time) but do help with body roll (where one side begins to lean).
- Link the suspension together
- Reduce body roll
- Keep the vehicle level
- Help evenly distribute weight
How to Tell If Your Sway Bar Needs to Be Replaced
Because they’re so simple, sway bars almost never break. But the bushings and links can wear down. As they do, you’ll notice weird squeaking sounds during cornering.
As your bushings and end links deteriorate, your handling will become worse. If not replaced soon, damaged sway bar bushings and end links can majorly damage your suspension.
Most people who replace their sway bars do so because they need one that better suits their driving style or build.
Off-Road Sway Bars
Sway bars are designed to keep your wheels level. While most off-road vehicles, like Jeeps, Broncos, and Raptors, benefit from this on the highway, it’s not great for off-roading. When crawling over uneven trails, you want a wide range of suspension motion and articulation.
Sway bars that are flexible or disconnect entirely are a major asset for off-roaders.
Disconnecting Sway Bars
The Jeep Wrangler Rubicon has an electronic front sway bar disconnect, and the feature will also be included on some Ford Bronco trims. While aftermarket sway bar end links can’t detach quite that easily, they still make it pretty simple. If you’re tired of carrying an 18 mm wrench with you on your trail rides, then these disconnect end links are a no-brainer.
Antirock Sway Bars
Most sway bars don’t offer enough articulation range to be trail-capable. But some sway bars are actually designed specifically for off-road use. These sway bars offer a greater range of motion.
What this means for off-roaders is that they get the balance of a sway bar without the loss of steering range. The disadvantage is that allowing more range of motion might cause more body roll while driving on the road.
Racing Sway Bars
If you drive a Mustang or other performance vehicle, then a larger sway bar can give you added stability. Stiffer bars can offer serious handling improvements.
The downside of stiff, track-style sway bars is that they can increase noise, vibration, and harshness (NVH).
Adjustable Sway Bars
Different vehicle models require specific sway bar sizes. Most aftermarket sway bars will offer adjustable settings. This allows you to select whether you want the stiffest possible setting or one that’s closer to stock. This is a perfect compromise for people who want to be able to track their Mustang as well as take it out on the street.
Drag Racing Bars
For drag racing, you usually don’t care if the front of your car leaves the ground. That’s why many drag vehicles will only have a rear sway bar. Rear-only sway bars will help you get a solid launch from the back tires.
Bushings and Links
The sway bar itself is connected to your suspension via end links and to your frame with bushings and brackets. If you’re not sure about swapping out your whole sway bar, these can also be upgraded for many of the same benefits.
If you lift or lower your vehicle, you’ll change your suspension geometry. You’ll need to change your sway bar end links to keep up with that. Adjustable end links allow you to adjust to your new height.
Are Poly or Rubber Sway Bar Bushings Better?
Swapping out a sway bar’s rubber bushings for polyurethane ones is a simple upgrade. Polyurethane is a stiffer material than rubber. This creates more responsive steering but does mean that you may see an increase in NVH in the cabin.
Poly bushings will also last longer than their rubber counterparts. Besides being more resistant to rot and deterioration, they also aren’t as affected by road salt or oil.
Better Handling for a Better Ride
Getting the right sway bars for your needs improves handling. Not only does that affect performance, but also your comfort and safety. That’s why suspension upgrades are so important.
Sway bars are a great suspension improvement you can install in your own garage. To get an idea of what’s involved, check out our guide for installing a sway bar on an S550 Mustang.
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