Are Shocks the Same As Struts?

Are Shocks the Same As Struts?

Struts and shocks are both integral components of a truck's suspension system, and while the trucking terms may seem interchangeable, the two parts have completely different functions – even though they share the same end goal. It is important to note that not all commercial vehicles have both struts and shocks. Some vehicles only have shocks. Some may only have struts, butthat does not mean that one component is better than the other. So, what is the real difference between struts and shocks? We're going to put the confusion to rest once and for all. Keep reading to learn the functions of struts and shocks as well as when to replace them on your heavy-duty truck.

Shock Absorbers

"Wow, that could have been worse," you think to yourself after hitting a pothole in the road. You think it is a good thing you have expensive tires. Not quite true. It is really a good thing you have shocks on your truck. Shocks are responsible for handling the tough blows of the road with ease and keep the vehicle from bouncing. Shocks are located near the tires and are vertical air or oil pumps that gently move up and down to keep vehicles grounded and recover from hard road impacts. A shock consists of a rod with a piston in a sealed tube filled with fluid. To help absorb impact, the piston works against the fluid like this: As suspension travels vertically, the fluid is slowly moved through tiny holes (called orifices). The graceful action from both the orifices and the fluid help to dampen suspension springs and allow for vehicles to stay in control, safely accelerate and brake, and handle unstable road surfaces.

Struts

On the flipside, struts are the structural part of a vehicle's suspension system and incorporate many suspension parts, such as coil springs and shock absorbers, into one compressed assembly to help support the weight of the vehicle. They work in harmony with shock absorbers to manage rough road impacts, too. Bad struts are what may affect the vehicle's steering and alignment thus throwing off wheel balance and causing abnormal tire wear.

Signs of Bad Shocks and Struts

Driving with bad shocks and struts is never a good idea, and will affect wheel and steering components. Look out for these signs of worn shocks and struts.

• If the vehicle bounces.

• If the front-end of the vehicle dives during braking and rear-end squats during acceleration.

• If you hear unusual noises, such as knocking, near the tires. (This may be from leaking shock absorbers.)

Pressing down on worn shocks and struts will cause them to move up and down faster rather than the slow-moving action we would rather see from new suspension parts.

When To Replace Shocks and Struts

Typically, shocks or struts should be replaced every 150,000 miles; however, vocational vehicles may require shock replacement after 75,000 miles. Changing shocks when you change tires or airbags may help prevent premature failures and additional component part costs, too. When looking for reliable suspension parts for your fleet vehicle, consider shopping brands you can trust such as Match Made, Gabriel and Monroe.