Shocks and Struts

I admit it.

I love Shocks and Struts.

Well, actually I love the feeling of hugging a windy and low-travelled road when driving my vehicle quickly around bend after bend. Sometimes I catch myself wishing that I could be driving the Autobahn or famous tracks on the 2015 Formula 1 circuit.

Whether you’re driving a sedan, convertible or Formula 1 car, maneuvering any vehicle around turns and dips in the road requires a lot more than expert handling and quick reflexes. It requires well performing shocks and struts with a full chamber of hydraulic fluid. I love shocks and struts because they dampen the impact of bumps, keep tires firmly pressed to the road and vehicle movement steady.

When a vehicle hits a bump – pistons are activated which push the hydraulic fluid through a series of valves to dampen the reciprocating bounce. A rebound spring then pushes the piston back into place; the whole process is similar to activating a Jack-in-the-Box. Hitting a bump is like the toy being sprung from the box. Your hand pushing the toy back in the box is like the rebound spring –pushing the piston to its original position.

There are 3 stages of activation for shocks and struts which occur based on the type of terrain the vehicle travels over and impact different valves within the hydraulic pump system.

Stage 1 releases this fluid at a controlled rate and is uses for everyday driving.

The stage 2 valve is for more active terrain or road conditions such as: dips, driveways, expansion joints, tight turns and sudden acceleration or deceleration. Dampening conditions for Stage 2 require more fluid and are managed by a set of flexible discs within the shock and strut chamber. The bigger the bump – the more they flex.

Stage 3 valve is for harsh impacts like curbs and potholes – where heavier dampening is critical to maintain proper tire and vehicle body control.

Typical characteristics of worn shocks is a harsh ride are due to the wear of the Stage 2 flex discs – when worn the metal in these becomes fatigued and flexes too easily, allowing fluid to pass to the stage 3 valve too soon. This activity can cause even the best driver to have a loss of tire and body control and can greatly reduce the effectiveness of your vehicle’s crash avoidance systems.

So when is a good time to check the condition of your shocks and struts?

A good benchmark to stand by is evaluating them with a road test every 50,000 miles. NAPA AutoCare technicians can inspect and test your suspension system and help you select the right parts to restore or improve your vehicle’s designed performance – and thrill of the road – again in no time!

Posted October 15th, 2015