How Does the Air Suspension in Your Truck Work?

Written by

CarParts.com Research Team

Automotive and Tech Writers

Updated on June 6th, 2024

Reading Time: 6 minutes
Summary
  • Heavy vehicles usually have an air suspension system that relies on pressurized air to lift the chassis.
  • The electronic control unit (ECU) controls the valves that deliver air to the air springs from the reservoir.
  • A typical air suspension system can improve a vehicle’s handling as well as its cornering speeds.

Have you ever wondered how your vehicle can support all the weight that’s put on it? Or why you’re comfortable in the driver’s seat even when driving on rocky or bumpy roads? Well, there’s a collection of parts in your vehicle that make all of this possible, and they can be found in the suspension system.

Suspension systems are engineered to absorb road shocks and keep the tires on the road. They also allow you to have maximum control over your vehicle while maintaining stability when turning or cornering.

These systems have come a long way since their inception. Today, there are several types of suspension used in vehicles. In this article, we’ll be covering the type that’s sometimes used in trucks—air suspension systems.

Suspension systems are engineered to absorb road shocks and keep tires on the road.

What is Air Suspension?

Air suspensions lift a vehicle’s chassis from its axle using pressurized air. These are typically powered by an electric pump or compressor that sends air into rubber bellows or air springs to raise the vehicle to a specific height.

This type of suspension is typically used in heavy vehicles⁠—such as trucks, tractor-trailers, passenger buses, and trains⁠—to prevent sagging when hauling or towing heavy cargo.

It allows for improved drivability, road handling, and ride comfort when driving on uneven terrain.

How Do Air Suspension Systems Work?

To keep the vehicle elevated, air is delivered from the reservoir to each air spring through valves controlled by the electronic control unit (ECU). As vehicle load increases or decreases, the height sensors attached to the suspension send signals to the ECU so the latter can adjust the struts by adding or releasing air.

In some vehicles, it is also possible to manually adjust vehicle height and create presets using controls located inside the cabin.

Benefits of Air Suspension Systems

There are plenty of advantages to having an air suspension system in heavy-duty vehicles like trucks. Here are the most common:

Improved Performance

An air suspension system can improve your truck’s grip and handling, generating higher corner speeds due to a lower center of gravity. Because you’re able to adjust ride height and lower your truck’s ground clearance, you can also achieve better aerodynamics with limited wind resistance.

Reduced Wear and Tear

Air suspension systems reduce vehicle bounce and vibration, which prevents its components and connected parts from wearing out prematurely. They help vehicle owners maximize the service life of key parts and avoid costly emergency repairs.

There are plenty of advantages to having an air suspension system in heavy-duty vehicles like trucks.

Adjustable Ride Height

One of the key features of an air suspension is that some systems allow drivers to adjust vehicle height depending on the load. For instance, more air can be added when towing heavy loads for smoother handling and deflate the air springs as needed for optimal ride quality.

This ensures that weight is evenly distributed across all tires. As a result, drivers enjoy optimal braking and steering control, reduced body roll, and a smooth ride.

Ride Comfort

With an air suspension system, passengers can sit comfortably without being bothered by noise, vibration, and harshness when driving on uneven road surfaces.

What is an Air Suspension Kit?

Air suspension kits contain the major components that make up the air suspension, including the compressor and air springs.

CarParts.com offers replacement air suspension kits for a variety of applications.

Air suspension kits contain the major components that make up the air suspension system.

Symptoms of a Bad Air Suspension System

Although having an air suspension system has a lot of perks, regular wear, as well as the damaging effects of rough road conditions, may require suspension parts to be replaced.

Keep an eye out for the following symptoms that may indicate a bad air suspension system:

Vehicle Sagging

If you notice that your vehicle is sagging or uneven, it might be time to replace parts of its air suspension system. This indicates that the suspension is unable to support the current vehicle load, which may affect your truck’s drivability and performance.

Running Compressor

Ideally, the compressor should stop pumping air into the air springs once the appropriate air pressure is achieved. If it continues to run, there might be a leak in one of the air springs or it may be experiencing a technical malfunction.

Either way, it’s best to have your vehicle checked by a licensed mechanic to properly identify what’s causing the problem.

Regular wear, as well as the damaging effects of rough road conditions, may require suspension parts to be replaced.

Bumpy Rides

If your drives feel bumpier than usual, it’s possible that the shock absorbers and air springs in your vehicle’s suspension may have worn down. Failing to replace faulty parts reduces the system’s capability to dampen road shocks and keep passengers in the cabin comfortable.

Leaning or Rolling

Faulty suspension components may cause your vehicle to lean or roll when cornering or making a U-turn. The vehicle’s weight shifts towards the outer corner as the system has trouble keeping the tires on the road.

Frequently Asked Questions (FAQs)

How Long Do Air Springs Last?

Air springs can last anywhere between 80,000 and 100,000 miles, depending on your driving habits. For instance, using your truck for regular towing and hauling may cause their air springs to wear faster compared to vehicles used for regular driving.

Air springs may also wear prematurely due to damage from road debris.

Will Air Springs Increase My Vehicle’s Weight Rating?

Adding air springs will not increase your vehicle’s weight rating. They will only assist in supporting heavy loads.

Failing to replace faulty parts reduces the system’s capability to dampen road shocks and keep passengers in the cabin comfortable.

Do Air Springs Come With an On-Board Compressor System?

Most air suspension kits come with an on-board compressor system, which allows you to inflate and deflate the air springs without going to a service station.

Will Hoisting My Vehicle During Maintenance Damage Its Air Springs?

Short-term service repairs such as tire or oil changes won’t damage the air springs. But if you need to keep your vehicle hoisted for a long period of time, it’s a good idea to use jack stands to support its weight and keep tension off the air springs.

On some vehicles, however, the air suspension must be turned off before they are hoisted to prevent system damage.

Where to Get Quality Replacement Parts for Your Air Suspension System

Unfortunately, even with the benefit of reduced wear and tear, air suspension system parts can still break down over time. Issues with your air suspension can affect your vehicle’s stability and controllability, so if you begin experiencing issues, it’s best to visit a trusted mechanic. If they tell you that you need new parts, you can turn to CarParts.com.

CarParts.com has you covered with our wide array of aftermarket parts. We sell parts from trusted manufacturers at different price points, all to suit your budget and needs. Use the built-in vehicle selector to help you narrow them all down. With this tool on our easy-to-navigate website, you’ll only be shown parts that are guaranteed to fit your vehicle’s make and model. What’s more, we offer fast shipping options that will deliver your new parts in as fast as two business days.

Don’t wait for your air suspension to fail. Purchase new parts for your air suspension system such as an air suspension compressor at CarParts.com today.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.