Speed bumps, or traffic calming devices, are raised structures installed on roadways to enforce lower vehicle speeds, typically in areas with high pedestrian activity like residential neighborhoods and parking lots. These structures vary in design, height, and materials. This article explores the potential negative effects these frequent road obstructions can have on a vehicle’s longevity and maintenance expenses, particularly when traversed improperly or frequently.
How Speed Bumps Stress Vehicle Suspension
When a vehicle encounters a speed bump, the suspension system is subjected to a sudden, intense vertical force that initiates a rapid compression and rebound cycle. This action places immediate strain on components designed to absorb and dampen road imperfections, such as coil springs and shock absorbers or struts. Repeated high-impact encounters significantly accelerate the rate of wear and tear, far exceeding the stress caused by gentle road undulations.
The internal mechanisms of the shock absorbers are particularly susceptible to this repeated jarring motion. Inside the shock, hydraulic fluid is forced through small valves to control the vertical movement. When a speed bump is hit too quickly, the fluid cannot pass through the valves fast enough to mitigate the force. This can lead to the bending of internal components or the premature failure of seals, resulting in fluid leaks and compromising the shock’s ability to effectively dampen movement.
The suspension’s rubber components, known as bushings, also experience accelerated degradation from constant, sharp impacts. These parts connect various suspension arms and links to the chassis, providing flexibility and isolation. Repeated stress causes the rubber material to fatigue and crack, which introduces excessive play or looseness into the system. This deterioration of rubber bushings and other articulated joints, like ball joints and tie rod ends, contributes to imprecise steering and can manifest as clunking or rattling noises.
Hidden Damage to Other Critical Components
Beyond the direct stress on suspension components, speed bumps pose a risk to other expensive parts of the vehicle, often resulting from improper clearance or forceful contact. Low-hanging undercarriage components are particularly vulnerable to scraping damage if the vehicle’s ground clearance is insufficient. This includes the exhaust system, which can be bent, cracked, or dislodged from its mounting brackets upon impact.
The oil pan, which holds the engine’s lubrication, and various plastic aerodynamic shields or spoilers also sit low and risk severe damage if the car bottoms out. A punctured oil pan can lead to a sudden loss of engine oil, resulting in catastrophic engine failure if not immediately addressed. Even less dramatic impacts can stress the connections in the power steering system, potentially causing leaks or damaging the steering rack mounts.
The vehicle’s tires and wheels can sustain damage when a bump is hit forcefully or at an angle. Hitting a bump at excessive speed can cause the tire to compress severely against the wheel rim, creating a pressure point that may lead to a pinch flat or a sidewall bulge. The sudden jolt can also damage alloy wheels, resulting in bent or cracked rims that compromise the tire’s seal and require replacement. Severe impacts can knock the vehicle’s wheel alignment out of specification, causing tires to wear unevenly and prematurely.
Driving Techniques to Minimize Vehicle Wear
Drivers can significantly reduce potential damage and premature wear by adopting specific techniques when traversing traffic calming devices. The most effective strategy involves drastically reducing the vehicle’s speed before reaching the bump, aiming for a slow, controlled roll-over. Slowing down allows the suspension system more time to react and absorb the vertical forces gradually, rather than experiencing a sudden, sharp jolt.
Avoid applying the brakes while the front wheels are actively on the speed bump. Braking causes the vehicle’s weight to shift forward, compressing the front suspension and limiting the travel of the shocks and springs. This action increases the impact force on the components. Drivers should complete all necessary braking before the wheels make contact with the incline of the speed bump.
For vehicles with a wider track or low ground clearance, some drivers may choose to drive over the bump with one wheel at a time, approaching at a slight angle. This method attempts to distribute the impact force across the suspension components sequentially, rather than simultaneously across the axle. However, this angled approach introduces lateral stress to the suspension and chassis, and is not a manufacturer-recommended technique.