Why Does My Car Bounce?
Asking yourself the question, “Why does my car bounce?” can have several answers, depending on what is causing the bounce to happen.
After all, you could just be driving down a bumpy road that hasn’t been taken care of. If there are no potholes in your drive or simple reasons for your car bouncing, it might be time to take a closer look.
Cars typically bounce because they’re responding to something in the road. While the rubber might help the car drive down the pavement smoothly, it can’t soften every bump in the road you might encounter.
However, there’s a big difference between driving over a few rocks and noticing a consistent bounce that has nothing to do with the road beneath you.
This article will help you troubleshoot your bouncing car to answer the question, “Why does my car bounce?” While not exhaustive, this list includes several major components that could be failing, which would cause the car (and you) to experience a bouncing sensation.
Unless you’re mechanically inclined, we also recommend visiting a mechanic to further diagnose the issue.
14 things that could cause the car to bounce
Car bouncing issues tend to come from beneath the car. If you have the chance to lift the car up and safely inspect underneath it, a visual once-over can sometimes pinpoint the issue. Broken suspension components are a dead giveaway when it comes to a bouncing car.
At the same time, internal components underneath the car can also be the culprit. In fact, finding the source of your vehicle’s bouncing could take disassembling parts of the vehicle.
Again, if you don’t feel comfortable checking into the problem yourself, it’s better to pay an experienced mechanic.
Worn or damaged shock absorbers or struts
Shock absorbers and struts keep your vehicle upright as you go through turns. When these components are worn or damaged, the dampening force each provides is lessened. This means you’ll feel more of a sway during cornering, especially at speed.
The same is true for braking as well. When you brake through a corner, you’ll feel the weight of the vehicle shift to the opposite side. Shocks and struts help maintain the car’s equilibrium when they’re functioning properly, but continuous wear can cause reduced performance.
Worn or damaged suspension components such as control arms or ball joints
Control arms and ball joints are components of your vehicle’s suspension that allow the car to move in a fluid motion.
Misalignment can cause many steering issues as different parts of the suspension run into one another. Most often, you can determine your control arms or ball joints are worn based on the sounds you hear.
This can be difficult to do if you’re inside the vehicle, but it’s easy enough to have a friend help you distinguish whether or not the bounce in your vehicle is due to a noisy control arm or ball joint.
Uneven tire wear or under-inflated tires
Tires are the contact between your vehicle and the road. If there’s something wrong with your tires, chances are your entire car is going to feel off.
If you feel bouncing in your car and aren’t sure where it’s coming from, checking the tires can be an easy way to identify or rule out a quick solution.
Tires are designed to wear specifically in a linear pattern. Uneven wear can mean that your car’s alignment is off or there’s something else wrong with your wheels.
Under-inflated tires can also have this effect. While under-inflated tires might help Jeeps cross all kinds of terrain, they’re not the best for your average city street.
You can easily find the proper inflation number on the inner door of your vehicle. Noted in PSI (pounds per square inch), this number tells you what you should inflate your tires to.
A few PSI won’t make a huge difference, but anything over 5 PSI is cause for concern. This is especially true if you haven’t deflated your tires yourself, as there might be a leak somewhere.
Worn or damaged steering components
It’s easy to think that simply turning the steering wheel will make your wheels go in the direction you want them to.
After all, that’s what they do when you get behind the wheel. However, there are many components within any vehicle’s steering system, most of them housed beneath the vehicle out of sight.
Steering components that are worn or damaged can easily turn a smooth ride into a shimmy and shake fest.
Like any other part on your car, steering components degrade as time goes on. This process is sped up if you drive for longer periods of time, hit curbs, or drive on rough roads.
If you’re behind the wheel asking, “Why does my car bounce?” you’ve probably got some type of damaged or worn steering component.
Bent or damaged wheels
Wheels are one of the many circular objects on a vehicle. However, it’s imperative that wheels remain circular so they can turn at an equal rate.
Bent or damaged wheels turn, but only for a short distance at best. If you have a bent or damaged wheel, this could be the reason you’re feeling bouncing in your car.
A visual inspection will likely reveal a bent or damaged wheel. However, it might be useful to take your vehicle to a local tire shop for inspection as well.
These shops will be able to tell you if your wheel is damaged or if there’s an issue with your tire instead.
Sometimes the issues is compounded and repairs are only needed for one component. Other times, the entire wheel and tire must be replaced.
Problems with the alignment of the wheels
Perfectly aligned wheels help your car drive down the road without wearing down components or causing mechanical failures. The inability to drive properly aligned can stress your suspension, cause improper tire wear, and even damage your wheels if not checked.
If you’ve ever looked at the wheel well of a vehicle, you’ll notice that several of the suspension components are close in proximity.
There are specific tolerances built in to keep those components away from one another, assuming the vehicle is properly aligned. When that goes out the window, metal components can clang together and cause a bouncing motion.
Leaks in the air suspension system
Using air to keep your vehicle upright is nothing new, but it can be the source of your car’s bouncing or swaying. Air suspension systems help to adjust the height of your vehicle, but a leak can spell disaster if it goes undetected. When all the air leaks out of your suspension, you’re stuck at the height at which your vehicle sits.
Most leaks in an air suspension system are easy to diagnose by the noise they make. The hissing you hear probably isn’t a stray cat that found its way underneath your car. However, seals and joints can also fail and cause not only a leak in your suspension but a shimmy in your vehicle.
Damaged or worn bushings
Various suspension components use bushings to soften movement, but too much slack can be detrimental. You’ll know worn suspension bushings by the swaying of the vehicle, especially if it accompanies clinks and rattles. When the bushings go, there’s nothing stopping all those hard mechanical components from hitting one another.
Most bushings wear out over time due to use. Heat, friction, and exposure to all the wonderful things that end up on the undercarriage of your vehicle can cause bushings to deteriorate.
As you do a visual inspection of your vehicle, check to see if suspension components move too freely. This can be a dead giveaway for a worn bushing.
Worn or damaged stabilizer links
Stabilizer link, sway bar, or anti-roll bar: whatever you call them, they help your vehicle experience less body roll through turns. When these links go bad, your vehicle can go from feeling tight as a drum to swaying through the corners like there’s no tomorrow.
Stabilizer links, like any suspension component, can sustain damage in many ways. While damaged stabilizer links won’t necessarily cause a car not to function, it’s not a good idea to drive on them for any longer than you have to.
When one component of the suspension goes, the rest can easily go with it.
Warped brake rotors
You won’t feel the typical up-and-down bounce of a vehicle with warped brake rotors, but you will notice the car pulling to one side as you brake.
Warped brake rotors typically stem from braking hard to overuse. That’s why it’s important to change your brake pads and rotors on a regular basis. The next time you need to stop and don’t want to feel a tug on the wheel, you’ll be thankful you took the time to replace your rotors and pads.
Worn brake pads or brake components
Your vehicle’s brake system includes several components that can cause your car to bounce, specifically when one of them fails.
If your brake piston sticks open or closed, you’ll feel the difference once you try to stop. Pressing the brake pedal can make this situation worse, especially if a component is worn and on the verge of failing.
If you think it is a worn or damaged brake component that’s at fault for your car bouncing, it can be easy to diagnose.
Simply do a test where you have someone outside the car, listening as you brake. If that person hears a noise or notices that something is off with one of the wheels, it can be easier to diagnose where the issue is coming from.
Worn or damaged engine or transmission mounts
Besides the frame of the vehicle, the engine and transmission are some of the biggest and heaviest components.
You can imagine what they would do to a car if they weren’t strapped down to the frame with specific mounts. That’s why it’s a good idea to check both engine and transmission mounts if you feel bouncing in your car.
These mounts act as cushions for the engine and transmission. Shifting gears and accelerating can stress both the engine and transmission while the various forces can move both components around in your vehicle. However, engine and transmission mounts keep both components tethered to reduce bounce and wear.
Excessive weight in the trunk or on the roof
Unladen, most vehicles rely on their suspension to keep the weight of the car moving around safely. However, if you put extra weight on the roof or in the trunk, that balance can be thrown off.
While less than one hundred pounds shouldn’t make a huge difference, more than that can have a significant effect on how your vehicle’s suspension responds.
For example, if you have 300 or more pounds on the roof, your car doesn’t have as much upward travel in the suspension as it would without that weight.
Depending on the age of the suspension and how much weight is in the vehicle itself, this extra weight could mean the difference between gliding over bumps and feeling every single one on the road.
Engine or transmission problems
If your car is having problems shifting gears, you’ll definitely notice. Either the car will refuse to go into gear, or you’ll experience a large clunk as it does.
This can be a sign of slipping gears on older transmissions that have deteriorated as the years went on. Your transmission may also clunk into gear due to loss of transmission fluid.
The same can be said for your engine, especially if something happens to put it off balance.
Shudders caused by the engine can cause your car to move about on the road. Engine failure can certainly wreak havoc on how the car handles, especially if it’s a violent failure.
If you suspect your car is having engine or transmission problems, and you feel a bounce or two, it’s a good idea to have the vehicle checked out as soon as possible. The more you can do to diagnose the issue early on, the less damage you’ll do.