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Once reserved for top-tier luxury vehicles, air springs have become more and more common in the auto industry over the last couple decades. As air suspension technology has improved and components have gotten less expensive, more automakers are putting them in their vehicles for all the advantages they offer.

In this article, we go over the basics of what air springs are and how they work. We also discuss some of the problems you may run into with air struts and how to fix them.

What Is an Air Spring Suspension?

Air spring suspensions are a type of active suspension system — or, a suspension that responds to changes in the road and movements of the vehicle by adjusting resistance. Other types of active systems include hydraulic suspensions and magnetic suspensions, but air rides are far and away the most popular.

How Do Air Springs Work?

Air springs work by using pressurized air to support the weight of a vehicle and provide damping. They are part of a computer controlled system that measures changes in the ride and makes adjustments accordingly. Here’s a basic step-by-step description of the process:

1. Ride height sensors mounted at each wheel constantly measure the chassis height relative to the road surface, sending their readings to a control module.
2. The control module determines what adjustments need to be made and instructs a manifold to distribute air as needed to any or all of the four wheels.
3. At the same time, an air suspension compressor generates more air for the system and pushes it to an air tank or the manifold.
4. Pressurized air travels through delivery lines and into the air springs when more resistance is needed. 
5. If the system needs to lower resistance, the air springs deflate and send air back through the delivery lines and into the manifold.

While there are several steps to this process, it all happens within a few seconds. It also runs continuously while the vehicle is in operation.

Air Spring Applications

The most common application for air springs from the driver’s perspective is to provide a smooth, comfortable ride. But air struts have other uses as well, including:

Adjustability: Air springs have to be able to adjust to function as intended. As a result, they also offer the ability to adjust ride height and resistance to different uses or driver preferences.

Additional support: Air struts can add more resistance to support heavier loads and limit the impact on the rest of the vehicle and prevent bottoming out.

Better turning: When drivers are going through turns, air springs can adapt to changes in force to keep the body level and distribute the weight of the vehicle evenly.

Improved towing: Air suspension systems can also help keep trailers, RVs, and other towables steady and level. Their responsiveness can compensate for wind and uneven road surfaces, preventing trailer sway.

Types of Air Springs

You’ll find several designs for air springs across different industries. But when it comes to cars and trucks, there are two main types of air struts: sleeves and bellows.

Sleeve Air Springs

Sleeve air springs are the more common design of the two types used in cars and light trucks. These springs use a straight cylinder made of durable rubber that extends and contracts to adjust ride height and resistance. Due to their more narrow design, they can easily fit into smaller spaces, allowing them to be used in a wider range of vehicles.

Sleeve Air Spring Components

Air springs with a sleeve design are made up of just a few components that include:

• Internally-mounted durable rubber cylinder
• Heavy-gauge rubber or synthetic rubber compound bag covering the internal sleeve
• Spring mount
• Body mount

Bellows Air Springs

The other type of air spring you’re likely to find on passenger vehicles is the bellows design. Bellows air springs are typically larger and heavier-duty than sleeve springs, which allows them to be used to haul bigger loads and support bigger vehicles. 

Bellows Air Spring Components

Air springs that utilize the bellows design have a slightly different set of components, including:

• One or more heavy-duty rubber convoluted air chambers
• Crimp rings at either side to secure the spring

Air Spring Repair

There are a lot of advantages to air springs, but the cost and ease of fixing them are not among them. Air springs require a perfect seal to function properly, so as they age and degrade over time, they can begin to leak. When this happens they can no longer do the job of supporting the vehicle and provide damping efficiently.

You may be able to patch small punctures or tears in air springs as a stopgap fix, but in most cases, they will need to be replaced. 

Common Air Spring Problems

Well-made air springs can last for quite a long time, but even the best will eventually wear out and need replacement. Here are some of the problems that can cause air springs to stop working as intended:

Punctures and tears: Road debris like rocks and glass can get kicked up into the vehicle chassis and perforate the rubber, causing small holes or tears. This leads to leaks, which degrades the performance of the air suspension system.Cracking or rotting: Even high-grade rubber can become brittle with age and begin to crack and leak. This can happen more easily in locations that see big temperature swings and places that experience extreme cold.Loss of seal: As air springs get older, they can lose their elasticity and eventually become loose around the seals. When this happens, air can leak out through these poorly-formed seals.

How To Choose an Air Spring Upgrade

It’s never fun to have to spend money to fix your car. But the good news is that when you do need to replace your air springs, you can take the chance to upgrade to better ones. 

At AirSuspension.com, we take pride in offering air spring replacements that often improve upon the OEM part. However, not all manufacturers can say the same. You’ll also find low-quality air spring components that can have just as many issues as the parts you’re replacing.

Here’s what to look for in an air spring replacement:

• Precise fit: Fit is everything with air springs, as they require a perfect seal to provide optimal performance. Some companies use the same part across multiple makes and models if they provide an “ok” fit. Avoid them and look for providers that make it clear that the product you’re looking at is designed specifically for your vehicle.
• Quality materials and construction: Some companies make air spring replacements that look the part at first glance, but are made with cheaper materials or assembled poorly. While it’s hard to tell from pictures on a website, look for companies that offer warranties on their products as a sign of confidence in their build quality.
• Brand-name components: Components from established manufacturers like ContiTech are a sign of quality in air spring assemblies. They tend to cost a little more, but the tradeoff is typically worth it.

Don’t Just Replace Your Air Springs — Upgrade Them

The air springs in your vehicle are responsible for the comfort, health, and safety of your vehicle. You shouldn’t trust that to just anyone. 

With more than 20 years of experience in the suspension industry, we know quality. Our team vigorously tests all of the products you’ll find on our site to ensure they provide long-lasting, high-level performance. When you shop for air spring replacements from AirSuspension.com, you also get the full support of our Certified Air Suspension Technicians who can help you find exactly what you need to give your vehicle the performance “lift” it deserves.