So, in the previous article, we’ve talked about two different concepts of enhanced suspension — air and hydraulic. Now, we’ll try to cover all essential bits of air suspensions to help you understand the concept so you can choose wisely. And even if you are not planning to actually get one and just want to know what it is and if you should buy a car equipped with some from the factory, don’t despair; we will talk about that too.
But let’s start with the basics…
How Do Air Suspensions Work?
Air suspension uses electronically controlled air pressure, a system of flexible polyurethane tubes or stainless steel lines, and air cushions to absorb the imperfections of the road surface and keep the vehicle straight and steady. The air cushions are also called air springs or airbags and replace the standard coil or leaf springs.
An air compressor is used to compress air into a tank and then distribute it to each airbag. The system controls the pressure automatically through electronic actuators and height sensors, but in most cases, the driver can also manually adjust it using in-cabin controls. Some models even come with a smartphone app!
What Are the Benefits of Air Suspensions
Why would you even think about changing your stock suspension, you may ask? Well, there are numerous benefits to air suspension, and here are the most significant ones:
- Air suspensions improve comfort and provides a cloud-like ride;
- Automatic leveling keeps your vehicle level when turning, accelerating, and braking. It can also keep the rear end from sinking when you have heavy cargo in the trunk;
- Better absorption of bumps and potholes extends the life of several suspension components;
- If you own a truck, then you probably know that the rear end tends to jump around when the bed is not loaded. This happens because the suspension is stiffer than on usual vehicles, enabling it to cope with higher loads. An air suspension will mitigate this effect and provide a more comfortable and predictable ride, no matter the circumstances.
Types of Air Suspensions
Semi air suspension
This type of air suspension supports the vehicle’s stock suspension and is usually used for trucks frequently hauling heavy loads. As such, it’s relatively cheaper since it doesn’t require a full swap. Some kits will save you a lot of time and are, in essence, plug-and-play systems.
Full air suspension
This type replaces the conventional suspension component (struts and coil springs), offering the complete package and all the benefits. With this system, you’ll get airbags all around, and you’ll be able to lower and raise your vehicle.
Also, there are two types of air spring styles that you can use depending on the purpose:
Type 1: Sleeve-style air springs
As the name suggests, the system looks like a sleeve as the nylon reinforced rubber forms an air-tight bag with an upper flange and lower endcap. The air extends the air spring allowing for greater height or simply holding the vehicle higher when loaded.
Pros
- The relatively smaller size makes this type of air spring easier to install;
- Suitable for street rods, light-duty trucks, and track cars.
Cons
- The smaller size limits its capability for heavier loads.
Type 2: Convoluted or Bellow-style air springs
This type of air spring is made out of heavy-duty, metal wire reinforced rubber and can come with one or two bellows.
Pros
- This type requires almost half the air pressure as sleeve springs do, thanks to the robust construction;
- More suitable for heavier loads.
Cons
- Requires plenty of space for proper installation.
OEM Air Suspension
If air suspensions are that glorious, why don’t all cars come with some from the factory? Lucky ones do have it. However, the higher production cost is a huge reason why most of us don’t get to enjoy the benefits of air suspensions. That is also why more expensive vehicles can get away with it; the extra investment simply doesn’t show as much in the total cost.
Still, OEM air suspensions differ significantly from the custom types, since they are specifically designed for each model. Don’t expect wild lowrider setups here as these cars ride on public roads, and carrying people around is their primary purpose.
Mercedes-Benz: Airmatic Suspension
Introduced 20 years ago in the W220 S-Class, Mercedes-Benz’s Airmatic suspension offered even better comfort and style to the already refined limousine. With tons of sensors and computers, it was by far the best OEM air suspension system at the time as it covered gazillion scenarios that one would experience on the road.
Auto leveling was one of the main pluses, as well as auto height adjustment, which lowered the car at higher speeds for better aerodynamics and improved fuel efficiency. The front axle also lifted for a higher approach angle, helping with speed bumps and there were also a few drive modes to choose from, each slightly adjusting the configuration to specific conditions.
Lincoln: Air Glide Suspension
Lincoln’s Air Glide system is quite sophisticated thanks to 12 sensors reading the road 500 times per second, preparing the suspension according to the road surface ahead. For example, once a pothole is detected, the sensors will stiffen the air shocks to reduce the stress on the suspension. Other benefits include lowering the height for easier entry into the cabin and loading gear in the trunk.
Tesla: Smart Air Suspension
Tesla’s Smart Air Suspension works similarly to the previously mentioned systems but uses GPS geofencing to preset the suspension according to previously driven routes. Hence, it can jack up the vehicle when approaching speed bumps or exiting a steep underground parking ramp and lowering it on the highway for better aerodynamics.
You’ll also get “over-the-air” updates as the speed threshold adjustments may change over time. Just keep an eye on potential reliability issues when buying a used Model S or Model X.
Volvo: Four-C Adaptive Air Suspension
Volvo’s Four-C Adaptative Air Suspension is available on several models as an option and does the usual lowering while entering the cabin (to 1.6 inches) and loading the cargo space (to 2 inches). On the other hand, it increases the clearance on rough terrain if you choose to drive off the main roads.
Lexus: Adaptive Variable Air Suspension
With Lexus’ Adaptive Variable Air Suspension, you can manually set up the vehicle’s height or choose between modes automatically adjusting the height based on different situations. For instance, the system could automatically lower your LS when opening a door, raise your RX while driving across a mountain or make sure that your GX handles just fine when towing your boat to that gorgeous house on lake Ozark you’ve bought with the money from that risky “investment.”
Also worth mentioning, Lexus’ system doesn’t have a reservoir—the compressor supplies the air pressure on-demand instead. While this may mean a slight delay when activated, it’s also a much more reliable alternative.
Jaguar: Active Air Suspension
As more and more EVs come to the market, suspensions become more and more sophisticated. One reason is the production cost we’ve discussed earlier, while the higher weight of EVs and their specific needs fill in the blanks.
For instance, Jaguar equipped its I-Pace with sleeve-styled air springs due to the compact design necessary with this model. Another big plus resulting from the air suspension is the decent ride quality despite the low-profile tires (255/40R22).
Porsche: Porsche Active Suspension Management
Porsche offers its PASM system on the Panamera and Cayenne, adding that special touch to already unique cars. PASM was explicitly designed to let you go full Jacky Ickx while driving on those twisty mountain roads to the top of Aspen. No need to mention that this is one option you shouldn’t skip on while ordering your next not-two-seater Porsche.
After all, Porsche doesn’t make bad suspensions.
Ram: Active-Level Four-Corner Air Suspension
The Ram’s air suspension lets you lower your truck by half, lift it two inches higher, or set it manually. Towing can be hazardous if you push the boundaries of a stock passive suspension, and Ram’s Active-Level suspension is there to save the day. It will keep your Ram level with your trailer and lower it to make the engagement process easier.
Audi: Adaptive Air Suspension
Audi’s famous Quattro all-wheel-drive system works hand in hand with the air suspension on higher-spec models. Of course, such a setup helps provide better ride comfort and off-road capabilities as usual but also benefits the Quattro system. Indeed, Audi’s adaptive air suspension improves the traction by keeping the wheels’ footprint optimal at all-time, resulting in better overall performance.
How Much Do Air Suspensions Cost?
This is a challenging question to answer as many variables affect the total cost — not to mention the manufacturers that seem cheap on paper but turn out to cost a lot more in fitment and maintenance.
However, suspensions are vital components, just like the braking and steering system, and you can’t improvise here. You can either end up with the car of your dreams by setting up your air suspension just right, or you can keep scratching your head trying to find why your tires are continually wearing out weird.
If your car didn’t come with stock air suspensions, you can get a conversion kit in most cases, which is by far the cheapest option, often for as low as $500. However, a couple of thousands north of that mark will get you a custom setup, while adding another thousand or two brings you those magic hands that will install all those rubbery bits and actually make it work.
Of course, if you know your way around cars and tools and want to spare a couple of bucks, you can always do it yourself. Still, be prepared to read how-to’s instructions and work under your precious vehicle for quite some time.
Last Words
Air suspensions are unique features and can transform your vehicle from good to great. Just remember that cheaping out is not an option here. The suspension affects other underbody parts and going for cheap Chinese alternatives can quickly turn into a nightmare. On the other hand, if you choose to buy a car with factory air suspension, make sure to have it inspected by professionals as factory setups are even more expensive to fix when broken.
