What is Air Suspension in Cars?
An air suspension for cars is a specialised type of suspension system that uses an electric compressor to pump air into various components of the system. The primary function of an airbagged suspension is to maintain the optimal ride height based on driving speed and terrain conditions.
Also known as a pneumatic suspension system, it plays a crucial role in providing a consistently smooth and comfortable driving experience. This advanced suspension technology is commonly found in high-end cars, passenger buses, trucks, and other heavy vehicles.
Air Suspension System Components
A typical car air suspension system consists of several key components, including airbags, compressors, air lines, valves, and solenoids. Each of these parts plays a vital role in adjusting the vehicle's ride height by regulating the flow and pressure of compressed air. Together, they ensure a smooth and adaptable driving experience. Let’s take a closer look at each component and how it contributes to the overall functionality of the system.
1. Airbags
An airbag is the most important component of the system that replaces the traditionally used coil springs. Depending on the manufacturer, the airbags can have different shapes. However, they are usually made of polyurethane and reinforced rubber to ensure toughness and structural integrity against sand and debris from the road.
There are three styles of bag shapes used in an air suspension system:
- Tapered sleeve: This small, cylindrical-shaped airbag can easily fit in tight areas. It allows easy placement and adjustable height of the system in a vehicle.
- Rolling sleeve: The rolling sleeve airbag also offers adjustable control and driving height to the vehicle. Due to their small diameter, these airbags are used in light-duty vehicles with space limitations.
- Double-convoluted bag: This type of airbag looks like an hourglass. The advantage of this type is the lateral flexibility it offers over the other two types.
2. Compressor
An air suspension system comes with a built-in compressor. It’s an electric pump that feeds air to the airbags. The compressor is usually placed either inside the trunk or on the vehicle's frame. Most compressors also contain a dryer, which is used to remove moisture from the air before pumping it through the suspension system.
The workings of a compressor involve drawing the air from the atmosphere, using the dryer to remove the moisture, compressing the air and sending it to the bags through narrow air lines. While simpler systems rely only on the compressor for pressure management, advanced systems come with an additional component called an air tank for the same.
3. Lines
Lines or air lines carry the air from the compressor to the airbags. Mostly, they are made of polyurethane or rubber composition. But you can get them replaced with custom steel air lines.
4. Valves
The system contains multiple air gateways called valves. They help to control the flow of air through different parts of the suspension system.
5. Solenoids
These are essential in electronic suspension systems to vent and fill airbags. For required adjustments, the system commands solenoids to open/close accordingly to adjust the air quantity in every bag.
How Does Air Suspension Work?
The working of an air suspension system revolves around controlling the air pressure and cruising height. The operation of airbagged suspension systems is managed entirely by the onboard airbags, compressor, dryer, and valves.
The air is collected by the compressor from the environment. The dryer uses a moisture-absorbent called a desiccant that dries the air before it gets pumped into the airbags through air lines. The pressure inside the airbags is managed by the required riding height.
What Are The Types of Air Suspension Systems?
Most air suspensions are pretty similar to each other. They differ with respect to the shape of their airbags and whether you can adjust them manually or electronically. Accordingly, there are four major types of airbagged suspension systems depending on their workings.
1. Convoluted Air Suspension System
These are air suspension systems with large rubber bellows. Such systems offer higher suspension capacity, making them suitable for heavy-load vehicles.
2. Rolling Lobe Air Suspension System
The rolling lobe suspension contains small-sized rubber airbags. These are usually used in smaller vehicles such as a sedan.
3. Coil Spring Bellows The Air Suspension System
This is a unique type of air suspension that contains coil springs. The rubber airbags are installed inside the coil springs to provide better drive quality and higher stability. Unlike mechanical springs, these air springs adjust the driving height by controlling the air pressure inside the bags.
Electronic Air Suspension System
An electronic air suspension system automatically controls the height of the vehicle. It uses undercarriage and speed sensors to adjust the suspension height. Typically, an electronic air suspension offers the following five height adjustments.
- Loading
- Highway
- Standard
- Off-road
- Off-road extended
The automatic system sets a suitable suspension height based on the vehicle speed. For instance, the “Highway” suspension setting usually works while driving at 80 km/h. However, off-road and off-road extended settings come into play at relatively lower speeds in rough road conditions.
Also, read: Car suspension: How does it work?
Advantages and Disadvantages of The Air Suspension System
Like any other machinery, the air suspension system also has its unique advantages and disadvantages.
Advantages of the Air Suspension System
Here are the advantages of air-bagged suspension systems.
1. Improved Driving Comfort
Cars with air suspension offer excellent driving comfort. The height adjustability allows a driver to obtain better control, especially in tough terrains. Passengers feel the minimal impact of the bumps on the road due to the compressed airbag suspension.
2. Less Vibration and Noise
Using air pressure adjustment, the suspension system experiences reduced vibration and harshness. The air pressure compensates for uneven surfaces, speed bumps, and potholes while driving without making much noise. It helps to have a pleasing, quiet drive and increases the lifespan of the suspension system.
3. Driving Versatility
With an electronic air suspension system, you can smoothly drive a vehicle in different road conditions. The suspension works effortlessly on highways, mountain roads, and even rough off-road terrains. An automatic air suspension can reduce the ground clearance of its vehicle while driving at high speeds. On the contrary, it can also increase the vehicle height for off-roading and city drives, which makes cruising much easier.
4. Load Versatility
The air suspension system lets you adjust the vehicle height based on the load as well. It ensures consistency of force distribution across the wheels to reduce the risk of rollover accidents on turns.
It also reduces the risks of vibrations that may cause load shifting, breakage, or damage while driving. As a result, carrying heavy loads becomes easier due to better control over the vehicle with air suspension.
5. Fuel Efficiency
Because of the adjustability of the suspension based on road type, you may experience an increase in the fuel efficiency of your vehicle. For instance, the lower drive height on highways reduces wind resistance and improves the vehicle’s aerodynamics.
On the other hand, a higher drive height on city or mountain roads makes turns and slopes easier to cover, resulting in saving time and fuel in the process.
Disadvantages of the Air Suspension System
Here are the disadvantages you may face with an air suspension system.
1. High Cost
The cost of buying an air spring suspension system is higher than a regular spring suspension. This is why only high-end or luxury cars come with built-in air suspensions.
2. High Maintenance
While you can rely on air suspension initially, it may require frequent repair work after long-duration or long-distance travel. You can’t avoid the repair needs, otherwise, it won’t be possible to keep the car stable while driving. Hence, maintenance is the necessary cost you have to handle to avail all the benefits of air spring suspension.
3. Mechanical Problems
The air suspensions also tend to face mechanical problems. Moisture and rust are common enemies that can damage the insides of the system. Moreover, the compressor may burn out if air springs start leaking air. Hence, regular check-ups and maintenance are necessary.
Air Suspension Cars in India
Due to their expense, you will find mostly high-end cars with air suspension in India. Here is a list of cars with air suspension available in India as of May 2025:
Model | Price (ex-showroom, Delhi) | Body type | Fuel type | ARAI Mileage |
BMW X7 | ₹ 1.29 - 1.33 Cr | SUV (Sport Utility Vehicle) | Petrol / Diesel | 11.29 kmpl |
Mercedes-Benz S-Class | ₹ 1.79 - 1.90 Cr | Sedan | Petrol / Diesel | 12 - 18 kmpl |
Land Rover Range Rover | ₹ 2.40 - 4.55 Cr | Luxury SUV | Petrol / Diesel | 13.16 kmpl |
Audi RS Q8 | ₹ 2.49 Cr | SUV | Petrol | 9 kmpl |
Frequently Asked Questions