There's nothing quite like the feeling of driving down the road and, suddenly, the back end of your vehicle collapses. A possible cause is that something in your suspension has broken. Suspension components gradually wear out – you may not even notice the ride and handling slowly getting worse. But a sudden failure is unnerving and will often leave you unable to drive your vehicle.
A broken spring can cause your suspension to drop suddenly. There are different types of springs, including coil springs, leaf springs, and air springs. Most vehicles these days use coil springs, and they look just like you think they'd look: a coiled-up metal spring like what you'd find if you took apart a ballpoint pen. Coil springs fail from rust (thanks, brine and road salt), trauma (think potholes, speed bumps, curbs) and just plain metal fatigue.
Leaf springs are often used in larger vehicles such as trucks and large SUVs. The design has been around since the early days of carriages, and they are designed to handle heavier loads. Since leaf springs are made up of metal plates stacked together, rust and fatigue are common causes of failure.
Another type of spring that can suddenly fail is an air spring. Air springs are rubber bags that hold pressurized air. They have an air compressor, an air reservoir, and height sensors. The advantage of an air suspension is that you can adjust the ride height, level loads, adjust handling characteristics, and lower the vehicle to make it easier to get in and out.
Eventually, the rubber in an air spring can rot out, or the airbag can be punctured causing the air to leak out all at once. Not only can the corner of the vehicle with the failed air spring drop suddenly, but it's also possible for the entire air system to lose air, allowing the vehicle to drop. Plus, compressors, solenoids, air lines, and sensors can also fail.
Your NAPA AutoCare Center technician can check your suspension components for rust, metal fatigue, cracks, or other worn or failing components. If you notice that your ride quality and handling is deteriorating, have us check your suspension.