Do you know that suspension systems came first even before the combustion engine was invented? Records show that ox-drawn carriages and horse-drawn chariots utilize some form of a suspension system. Vehicle suspension systems were not just created with riding comfort in mind. They were made considering the safety of the vehicle users and passengers. 

Vehicle suspension systems dampen NVH or noise, vibration, and harshness coming from the various moving parts and the rolling motion of the vehicle on the road. Several suspension systems were developed starting from the leaf spring, coil spring, hydraulic, and airbag suspensions. 

Some cars or trucks have built-in airbag suspensions. However, aside from upgrading to some heavy-duty wheels, putting in some airbag suspensions helps your vehicle evenly distribute a more significant load. It is why this type of suspension system is popular on trucks, SUVs, and 4x4s. However, they are also applicable for most passenger cars. Coil springs are common for most vehicles, but this should not be your basis for not exploring your options for going airbags. 

What is an airbag suspension?

Airbag suspensions are powered by, you guessed it right, air, unlike coil springs that use massive metal springs and hydraulics that use fluid and pressure. The system utilizes an onboard electronically controlled or engine-powered compressor to pump air into bags up to a certain amount of pressure. These bags are made of textile-reinforced rubbers or polyurethane. They are tough enough to withstand the air pressure from the inside and the load and movement of the vehicle. The air inside the bags replaces and does the springing action of coil springs. It is also called air suspensions, air bellows, or air springs. Different manufacturers also have their own terms for airbag suspensions. 

Do not let airbag suspension technology intimidate you. It simply replaces the coil spring. Furthermore, there are even airbags in the market that can be added to the coil spring to assist them with weight lifting for your vehicle. 

How does it work?

When you press down on an inflated balloon, you'll feel it resists the force you apply to it. This same principle applies to airbag suspensions. The trapped air absorbs and dissipates the stress and impact from the outside. Like coil springs, rubber bellows also compress the vehicle's weight and any additional load. The air pressure increases when the air volume decreases due to the compression. More air pressure also means stiffer suspensions. It is also why airbag suspension is very much suited for heavy lifting. It is why some suspension lift kit options incorporate airbags in their system. They also prevent the rear part of the vehicle from sagging when you load up your truck with heavy stuff. 

Most modern cars apply an electronically controlled air suspension (ECAS) system. It involves many different components and performs many features. With just a press of a button, you can pump more air into the airbag as deemed necessary. The vehicle's height can be maintained even with added load. ECAS is equipped with the following parts:

  • Vulcanized rubber air springs for heavy-duty use on each wheel
  • Air compressor
  • Compressed air storage tank
  • Valve blocks
  • Terrain and height sensors
  • ECAS computer controls
  • Desiccant to keep the air free from moisture

Benefits of airbag suspensions

Innovations happen for a reason, and usually to solve particular problems. We can say the same for air suspensions as it has many advantages for car users. Yet, of course, it also has its drawbacks. Let's take a look at them.

Ultimate comfort - Airbag suspensions effectively absorb stress and vibration, giving the vehicle user ultimate riding comfort. They significantly reduce the noise, vibration, and harshness transferred from the road. These elements may cause fatigue and discomfort to the driver and passengers. Even going over speed bumps is barely noticeable with airbag suspensions. Overall, airbags result in a smoother ride and are prevalent among luxury vehicles. 

Adjustable driving height - Load and speed significantly affect the vehicle's driving height. It is not uncommon to experience sag, especially when your car or truck carries a heavy load. Unlike coil springs, more air can be added to airbag suspensions to compensate for the added load. As more air is added, the airbags decompress and return to their original form and height. The additional air pressure also stiffens the suspensions. They effectively restore ample ground clearance, especially for offroading vehicles. 

On the other hand, the vehicle's height can also be lowered. It significantly helps passengers to climb up easily. Additionally, a lowered car produces less drag optimizing fuel economy, not to mention the added appeal to its stance.

Less tendency of bounce overs - Trucks with shorter wheelbase have tendencies to bounce over on rough terrains when empty. This issue is less likely to happen when using airbag suspensions. 

Versatility - Because the height, pressure, and stiffness are adjustable, you can do so as you see fit to your intended use. You may want to drive through valet with a lowered and sophisticated look for your vehicle paired with some new oe performance wheels. On the other hand, simply increase the height to gear up your truck for an offroading trip. 

Disadvantages

Costs a lot more - Air suspension systems, especially those with specialized sensors, entail more technology to operate. Each one adds to the overall cost making them considerably way more expensive than coil springs. You may notice that vehicles available in the market with built-in airbag suspensions are much more expensive than those using coil springs. If you plan to change your existing suspension system, installation, modifications, and upkeep are also added expenses. 

Maintenance - This suspension system also involves more moving parts needing checks. Think about it - coil springs against airbags, compressor, air tank, air pipes, valves, etc. The rubber air spring wears faster than the good old coil springs depending on the quality. They can leak or get brittle. The air pipes can also leak due to corrosion or normal wear and tear. Plus, whichever part of the system leaks, the entire airbag suspension system may malfunction. You can have them checked once in a while for wear and tear or leaks. The water trap also needs to be drained every now and then. 

Installation - If your vehicle does not have a stock air suspension system and wants one installed, you're in for a hefty cost, waiting time, and numerous procedures. The installer may also need to drill holes to install brackets to securely mount the air compressor, air tank, and other components. 

Types of Airbag Suspension

There are many options for airbag suspensions. They differ based on use, weight rating, and many other aspects. However, they can be grouped into two main types:

  1. Sleeve type - This type resembles a sleeve made of durable textile-reinforced rubber with a crimp ring and a plate at each end. The rubber material is flexible enough to fold when compressed and unravel again when the airbag is filled with air increasing the vehicle's height. Sleeve-type airbag suspensions generally have smaller diameters for easy fittings. They also usually have less weight capacity than the convoluted type. 
  1. Convoluted - This is also known as the bellow type because of its structure. It can be a single-convoluted or double-convoluted air spring. Generally, it is made of metal-reinforced rubber for added durability. It has more weight-lifting capacity as well. 

What to consider when purchasing airbag suspensions

Purpose - Like any other car or truck accessories, airbag suspensions are available in different specifications suited for specific purposes. Let's say you use your vehicle ultimately for hauling and towing; then, you need to find airbag suspensions that can handle the load. If you use your truck for offroading and need the height for more ground clearance, get the set designed for that purpose. 

Vehicle specifications - This aspect also greatly matters when it comes to fitting the airbags and the entire suspension system. You might be using wide wheels that may rub against the airbags, which can be detrimental to their function. Additionally, find out if your car or truck has space for all the other air suspension system components, especially if you wish to install it yourself. When in doubt, leave the installation part to the professionals. 

Cost - To set your expectations, air suspension systems are not cheap. If you have a particular budget and sticking to it means you'll have to cut corners with the components, maybe it's better to wait it out. Quality generally comes with a price. Quality also means you are less likely to encounter unnecessary issues and premature breakdowns. Make sure to check suspension systems from reputable brands and sellers. 

Vehicle modifications have tradeoffs. It is up to you to weigh the pros and cons and decide the airbag suspensions for your needs. Of course, professionals can help out with what you can expect. Also, leave the installation and maintenance to them if you have limited knowledge about air suspension systems. Airbag suspensions may seem complicated because of their components and the principles behind how they work. However, they are developed for excellent reasons that are pretty enjoyable once you have experienced having them.