Getting to Know Your Suspension

How Does A Suspension System Work In A Semi-Truck?

The suspension system is one of the most important systems in your semi-truck. A proper suspension system contributes to the handling and stability of a vehicle while you're driving. Without a working suspension system, you'll have difficulty supporting the load being hauled by the truck.

While the purpose of car suspension and truck suspension systems are the same, the system itself is different between these two types of vehicles. Read on to learn more about the suspension system in your semi-truck!

Parts Of A Semi-Truck Suspension System

There are several components that make up the suspension system in your semi-truck. Including shocks, airbags, torque rod arms, leaf springs, u-bolts, bushings, and stabilizers, your truck's suspension is a complex system of parts that work together to help keep your truck stabilized.

Systems that make up your suspension include:

1. Shock Absorbers: Shock absorbers work with the springs to absorb the shock caused by bumps in the road. ( The Suspension's Seven Parts)
2. Airbags: Airbags provide additional support at the front or rear of your vehicle, allowing you to maintain a level ride height when hauling a heavy payload.
3. Torque Rods: Torque rods are suspension links that are meant to limit the movement of the axles without limiting suspension articulation. ( Torque Rods and Torque Arms)
4. Leaf Springs: Leaf springs are a basic form of suspension made up of layers of steel of varying sizes sandwiched one upon the other. ( The Advantages And Disadvantages Of Leaf Springs)
5. U-Bolts: The U-bolt provides the force required to clamp the leaf spring and related components firmly together. ( What Does A U-Bolt Do?)
6. Bushings: Bushings are mounted on suspensions and steering joints to absorb road bumps, control the amount of movement in the joints, and reduce noise and vibration. ( What Problems Do Worn Suspension Bushings Cause?)
7. Stabilizers: The purpose of a stabilizer is to try to keep the truck's body from rolling in a sharp turn. ( How Do Stabilizer Bars Work?)

What do Semi-Truck Suspensions Do?

Suspensions are responsible for a number of tasks including keeping the vehicle from rolling, absorbing impact, assisting with additional weight, and equipment protection. When it comes to commercial vehicles, the suspension system plays a pivotal role in helping provide stability on the road that heavy-duty vehicles need.

The functions of a suspension include:

1. Keep the vehicle from rolling: In order to keep your semi-truck from rolling, the suspension system uses a system of stabilizing components. Since semi-trucks tend to be extremely heavy and carry additional weight, the suspension system works to keep the truck stable on uneven roads.
2. Absorbing impact: It's also the suspension's job to make sure that the truck can absorb impact. The suspension assists in cushioning the ride so that the cargo and equipment remains protected over bumps and other imperfections in the road. Cushioning the ride also helps improve driver comfort.
3. Assisting with additional weight: If you drive a semi-truck then you will definitely be hauling extra weight with you on the road. Your suspension helps keep you stable while you are transporting heavy loads.

How Does A Semi-Truck Suspension Work?

Suspension work on the basic principle that isolating the body of the vehicle from the wheels provides a smoother ride for the driver, cargo, and equipment. Today's suspensions use a form of spring that flex and allow the wheels to move up and down on uneven surfaces without disturbing the cargo.

A "spring rate" refers to the stiffness of the spring in the suspension system. Even though a lower spring rate offers the driver a more comfortable ride, it is not perfect for the truck's handling or stability. Since the weight of the load will push the springs down even further, this poses an issue for semi-trucks that are hauling heavy loads. To rectify this, suspension systems designed with a higher spring rate give the vehicle better handling, stability, and capacity.

For trucks with traditional leaf springs, a higher spring rate equates to a suspension that is quite firm and creates a rough ride for the driver, the cargo and the vehicle itself.

Read More About Semi-Truck Suspensions!

If you would like to know more about the suspension system in your semi-truck, you've come to the right place. In order to provide you with a little more knowledge on what goes into your commercial vehicle's suspension, our experts have written the following articles for you to look through.

1. Getting To Know Your Suspension: Shocks
2. Getting To Know Your Suspension: Torque Rods
3. Getting To Know Your Suspension: Leaf Springs
4. Getting To Know Your Suspension: U-Bolts
5. Getting To Know Your Suspension: Bushings
6. Getting To Know Your Suspension: Stabilizers

Shop for Suspension Parts Now!

If you are ready to purchase an aftermarket suspension part, we have everything you could possibly want. With brands like Monroe, Gabriel, and Match Made, you won't have any issue finding the right parts for your semi-truck.