Shocks and struts are vital components of your vehicle’s suspension system, playing a crucial role in maintaining consistent tire contact with the road. This contact is paramount for optimal steering, handling, and braking performance. If your tires lose grip, your ability to control your vehicle is significantly compromised. High-quality ride control products like Shocks Struts deliver numerous essential benefits:
- Managing excessive vehicle body and tire movement
- Minimizing vehicle bounce, body roll, and sway, as well as brake dive and acceleration squat
- Ensuring consistent steering and braking responsiveness
- Helping to maintain proper wheel alignment
- Contributing to the reduction of premature wear on tires and other suspension components
Shocks vs. Struts: Understanding the Key Differences
While the terms “shocks” and “struts” are often used interchangeably, they are distinct components with unique functions within your vehicle’s suspension. Both shocks and struts contribute to ride comfort and handling, but they achieve this through different mechanisms and structural roles. Shocks are individual damping components, whereas struts are integrated structural parts of both the chassis and suspension system.
The Role of Shocks in Ride Control
Contrary to common misconception, conventional shock absorbers are not designed to bear the weight of your vehicle. Instead, the primary function of shocks is to control the movement of the springs and suspension. This is achieved by converting the kinetic energy generated by suspension movement into thermal energy, or heat, which is then dissipated through the hydraulic fluid within the shock absorber.
The resistance generated by a shock absorber is directly related to the speed of the suspension movement and the size and number of small openings, known as orifices, in the piston. Modern shocks are velocity-sensitive hydraulic damping devices; this means they provide greater resistance as the suspension moves faster. This velocity sensitivity allows shocks to adapt to varying road conditions and effectively reduce:
- Vehicle bounce, ensuring a smoother ride.
- Body roll and sway, often exacerbated by worn shocks that lose their capacity to manage weight transfer effectively.
- Brake dive during deceleration and acceleration squat when speeding up.
Shocks operate based on the principle of fluid displacement during both compression and extension cycles. Typically, shocks in cars and light trucks offer more resistance during the extension cycle compared to compression. The compression cycle manages the motion of the vehicle’s unsprung weight (wheels, tires, etc.), while extension controls the heavier sprung weight (vehicle body).
Exploring Shock Components
At their core, shocks function as oil pumps. Inside a shock absorber, a piston is attached to the end of a piston rod and operates within a pressure tube filled with hydraulic fluid. As the suspension moves in response to road conditions, the hydraulic fluid is forced through the small orifices in the piston. These restricted openings limit the amount of fluid that can pass through the piston, thereby slowing down the piston’s movement. This controlled piston movement, in turn, dampens spring and suspension motion.
The Function of Struts in Suspension Systems
Struts represent a common type of damper utilized in many modern vehicles, particularly those with independent front suspension and front-wheel-drive configurations, as well as some rear-wheel-drive models.
A strut is more than just a damper; it’s a significant structural element of the suspension system. It effectively replaces the upper control arm and upper ball joint found in traditional suspension designs. This integrated design makes struts lighter and more space-efficient compared to separate shock absorber setups in conventional suspensions.
Struts perform two primary functions. First, similar to shocks, struts provide damping to control spring and suspension movement. Internally, a strut incorporates a shock absorber-like mechanism. A piston attached to a piston rod works against hydraulic fluid to manage suspension motion. Like shocks, the internal valving in struts creates resistance to the forces generated by the up and down movement of the suspension. Struts are also velocity-sensitive, meaning their resistance adjusts based on the speed of suspension movement.
Secondly, unlike shocks, struts offer crucial structural support for the vehicle’s suspension. They support the vehicle’s spring, maintain tire alignment, and handle a significant portion of the side loads exerted on the suspension. Consequently, struts have a profound impact on ride comfort, handling, vehicle control, braking efficiency, steering precision, wheel alignment, and the wear rate of other suspension parts.
Strut Assembly: Components Breakdown
Typically, a strut assembly comprises a strut housing, which provides robust structural support, and an internal damping unit to manage spring and suspension movement. In most strut designs, the lower part of the strut housing connects to the steering knuckle, which is further linked to a lower control arm via a lower ball joint.
A complete strut assembly is designed for ease of replacement, providing all necessary components in a single, pre-assembled unit. This includes the strut housing, the damping unit, and a coil spring that is essential for supporting the vehicle’s weight.
Identifying Shocks or Struts on Your Vehicle
Every wheel on your vehicle is equipped with either a shock or a strut to manage ride control. Your vehicle might utilize shocks on the front axle and struts on the rear, or vice versa, depending on the design. The key takeaway is that each wheel incorporates a ride control component to ensure optimal handling and stability. Understanding whether your vehicle uses shocks struts, or a combination, is the first step in proper suspension maintenance and ensuring vehicle safety.
