Keep your suspension smooth with reliable replacement air springs and leveling valves. Whether you’re hauling a light or heavy payload, your semi truck suspension needs to stay level. That’s where air springs and leveling valves come in.

The Importance of Semi Truck Leveling Valves

These parts help your semi-truck or trailer automatically adjust to changing loads—keeping your ride height stable and your truck handling like it should.

What’s a Leveling Valve & How Does It Work?

A leveling valve (also called an air suspension valve or air bag leveling valve) is the brain behind your air ride system. It controls how much air flows in or out of your air bags. Here’s what it does: If your trailer sags under heavy weight, the valve senses the drop and adds air to lift it back up. If your trailer rides high after unloading, the valve bleeds out air to bring it down to the right height. No guesswork. No manual adjustment. Just consistent ride height—automatically.

Why Upgrade or Replace your Valve?

Over time, these valves wear out from constant exposure to road grime, moisture, and vibration. A failing level valve can lead to: - Uneven ride height or leaning suspension. - Excessive bouncing or poor shock absorption. - Sluggish response when loading or unloading. - Hissing air leaks near the valve area. If you're noticing these signs, it might be time for a replacement. And while you’re replacing the valve, it’s the best time to install new push-to-connect air line fittings for a leak-free seal. You can also get an even better ride by replacing worn-out shock spring parts located near the air springs.

Where Is It Located?

Most leveling valves are mounted on the frame near your rear axle and are linked to the suspension via a control arm or linkage rod. Some trucks also have a valve on the steer axle.

Shop the Best Air Ride Leveling Valve Options

Explore our aftermarket selection of universal semi truck valves and components designed to meet or exceed OEM performance standards. Our inventory includes: - Mechanical and electronic leveling valves. - Heavy-duty air suspension valves for Class 8 trucks. - Mounting brackets, linkage arms, and hardware kits. - Compatible with most major makes and models (Peterbilt, Freightliner, Kenworth, International, and more). These replacement valves are easy to install and built for long-lasting performance under the toughest conditions. You can also extend the life of your valves with clean, dry air simply by upgrading your air-dryer housing components. Take the guesswork out of your suspension setup. Shop semi-truck air ride leveling valves and accessories at 4 State Trucks—your source for reliable, road-tested heavy-duty truck valve solutions.