The job of a car’s suspension system is to as smooth a ride as possible by keeping the tires in contact with the road and the vehicle steady by absorbing the energy from uneven roads and other kinetic impacts (bumps and jolts). The suspension system encompasses many mechanical components like axles that connect the wheels to the frame, as well as integration with the steering system to provide vehicle control and the braking system to bring the car to an even stop. Most cars have a suspension system for both their front wheels and back wheels. The most common suspension systems are independent suspension or dependent suspension.
·Independent Suspension
Independent suspension systems are when the back or front wheels move independently on the front or rear axles with no connection between the two sets of wheels on either side of the axle. The wheels respond independently of each other and can have different reactions such as when one wheel hits a bump in the road, only it will be affected but not the wheel on the other end of the axle. Independent suspension offers a smoother, more comfortable driving experience.
· Dependent Suspension
Dependent suspension systems have a solid axle fixed along the frame’s width, joining the set of wheels on the left and right sides and they operate as a single unit. The connected wheels act in sync for turns and bumps, responding the same to any event. Dependent suspension is best for rough terrain and roads so many rear-wheel-drive cars and SUVs have dependent suspension as their primary suspension system.
Axles and Suspension
A car axle or axle shaft is the mechanical link transferring power and torque from your engine to your wheels so they rotate and move the car. Both front and rear axles are vital parts of your car’s driving, steering, and braking. Axles work the same in both manual and automatic transmission vehicles and passenger cars and light trucks have two axles with four wheels, one pair in the front and one pair in the rear that support the weight of the vehicle. There are several types of axles, the most common is the transaxle, which encases the transmission and a differential. Axle Parts include:
· Axle Housing and Carrier Assembly
· Loaded Beam Axle and Stub Axle / Rear
· Torsion Bar
Shocks, Struts, Springs, and Suspension
Shocks and struts work with suspension springs to balance the car and absorb the shock of road connection with your tires. Every wheel on your car has either a shock or strut that facilitates steering, road handling, and braking. Most vehicles today only use struts, but some use a combination of struts on the front wheels and shocks on the back wheels.
Shock absorbers ensure a smooth ride over rough terrain by reducing (damping) the amount of vibration in your car.
Like shock absorbers, struts perform damping, but they also offer structural support for the vehicle suspension, supporting the springs and holding the tires in aligned positions making sure the tire tread grips the road.
Springs bend and give to absorb the impact when you drive your vehicle over bumpy roads. Common types are Coil and Air Springs. Air springs have an air-filled cylindrical chamber and coil springs are tense bars of metal wrapped around an axis. Additionally, Leaf springs are metal layers, bound tightly into a single unit, that have mostly gone out of use except for heavy-duty vehicles and trucks (Leaf Spring / Front, Leaf Spring / Rear).
Miscellaneous Suspension Parts
Along with axles, shocks, struts, and springs, a car’s suspension system has many different connection points that link and support all the different parts together. For example, the frame of the vehicle is connected to the wheels by the control arms (Lower Control Arm / Front, Lower Control Arm / Rear, Upper Control Arm / Front, Upper Control Arm / Rear). At the end of the control arm is a ball joint. Ball joints are connected to the steering knuckle with wheel bearings attaching the knuckle to the wheel (Spindle Knuckle / Front). The wheel bearing allows friction-free movement and rotation of the hub assembly for smooth tire and wheel rotation (Wheel Bearing / Front, Wheel Bearing / Rear). Wheel bearings guide and support shafts and axles. Other parts include Stabilizer Bar, Knee / Front, Suspension Compressor Pump, and Independent Rear Suspension Assembly as well as tie rods, bushings, and joints that serve to link smaller suspension parts to the bigger suspension parts.
While the steering system is not a direct component of the suspension system, the steering wheel is connected to the suspension system by the steering column. The steering column runs through the engine block and connects with the universal joint which connects with the steering shaft that connects to the rest of the system on the axle. Together, the steering system and suspension make the wheels and tires turn and drive. Parts of the steering system include steering wheel, steering column, Steering Gear Rack, universal joint, Drive Shaft / Front, Drive Shaft / Rear, rack housing, axels, and tie rods. Most cars today use a rack and pinion steering system with power steering. Power steering is either hydraulic or electric/electronic an the systems can include hydraulic fluid, Power Steering Reservoir, Power Steering Pump / Motor, hoses, and lines that connect to the rack and pinion.
The brake system in all cars is operated by the driver pushing down on a pedal to slow or stop the vehicle. The brake master cylinder houses the car’s brake fluid which is dispersed evenly to all four wheels when the brake is applied, bringing the car to an even stop. This is called a hydraulic braking system. The two most common brakes are drum brakes and disc brakes, with disc brakes being the most used system. The disc or rotor is mounted inside the wheel and turns within a bracket called a calliper that holds the brake pads in place. Anti-lock brakes (ABS), more common with disc brakes than drum brakes, prevent wheels from locking or skidding, no matter how hard the brakes are applied. Steering stays under control and stopping distances are reduced with ABS. Additional brake system parts include Braking Plate / Front, Hub, Pedal / Brake / Clutch and Power Brake Booster.
A good suspension system is an important safety feature of your car with benefits like:
Improved handling, braking, and cornering
Prevents premature tire wear by keeping the tires in steady contact with the road
A more stable and comfortable ride with less bounce, roll, and sway
Bumpy, uncomfortable ride
Difficulty steering or pulling to one side
Drifting when cornering
One side of the car feels lower
Front dipping when braking or rocking after stopped
If you’re experiencing any of these negative actions, you should have your suspension system, including shocks, struts, brakes, and steering checked to see where the problem is and get it fixed before you’re in an accident or left stranded. LKQ Online has a vast inventory of genuine OEM used car parts as well as new aftermarket parts for upgrading or repairing your car’s suspension system. Save money and ensure safe travels with guaranteed fit and warrantied new and used auto parts that ship fast directly to you or the auto shop you choose.