Why Is My Car Shaking?
Nobody likes the feeling of being broken down on the side of the road with no auto repair shop in sight. Oftentimes, these instances can be avoided with regular vehicle maintenance. While it is typical for some parts to wear down over time, sometimes it costs you much more to solve a bigger problem that could have been avoided with regular vehicle maintenance.
One of the most common problems that drivers experience is vehicle shaking. It can happen while accelerating or braking and there are some common causes as to why this happens.
Top Reasons Your Car May Be Shaking
There are several explanations for car shaking when braking:
- One of your tires could be badly “out of round”
- A wheel could be unbalanced having lost its counterweight
- Your car’s front-end alignment could be way out of whack
- Your car’s steering might suffer from a loose control arm or damaged knuckle
- You might have a damaged axle shaft that’s acting up
- You might even have a case of loose lug nuts, giving the wheel a chance to wobble that becomes especially noticeable as you slow down
Vibration is usually caused by an out-of-balance or defective tire, a bent wheel, or a worn driveline U-joint. You may find that the car shakes the car in an up and down motion. You may feel the vibration through the seat, the steering wheel, or even in the brake pedal.
Stop, look and listen
While there are many possible causes of vibration, observing under what conditions the vibration happens will help you and your mechanic find the source of the problem. Here are some things to look for:
- Does the vibration get worse as the speed increases?
- Does it happen only at certain speeds? If so, what speeds?
- Does the vibration seem to be concentrated in the car seat?
- Is there any abnormal noise when the car shakes?
- Does the car vibrate while standing still with the engine running?
- Does the movement seem to be concentrated on the steering wheel?
Let’s take a look at some of the possible causes of vibration.
1. Engine Problems
There are a few parts within a vehicle’s engine that could cause a car to shake if they malfunction. These include the spark plugs and engine air filter. Check the spark plugs and their connections. As a general rule, spark plugs last for about 80,000-100,000 miles, depending on the make and model of your vehicle.
If the spark plugs are okay and their connections seem sound, then check your air filter next. A dirty or clogged engine air filter can starve the engine of oxygen and/or fuel that it needs to run properly.
A broken or loose engine or transmission mount may be the culprit or even a broken radiator fan. A broken fan will usually be out of balance and cause a noticeable vibration when it is rotating.
However, most cars have electrically operated radiator fans that only operate when the coolant temperature surpasses a certain level.
2. Brake Problems
If vibration is occurring when you are applying the brakes, the problem is likely related to your car’s front brake mechanism as the front brakes take the most stress when the car’s brakes are applied. There are a few parts on front disc brakes that need to be replaced every so often named, including the pads and rotors.
The rotor is the round metal disc that attaches to the wheel. Over time it can become warped from heavy wear and tear. There are pads that press against the rotor in order to slow down the vehicle and these pads need to be a certain thickness in order to work properly.
If the pads have become too worn, it can cause the vehicle to vibrate. The caliper helps to squeeze the pads against the rotor to slow down and stop the vehicle. All vehicles vary on timelines for when brakes need to be replaced.
On average, they should be replaced every 50,000 miles but many makes and models can last longer. Consult your vehicle’s owner’s manual for a more accurate timeline for replacement.
In addition, whenever you get an oil change, have your mechanic visually check the condition of your pads and rotors. These professionals can give you a better idea of when replacement is necessary.
3. Axle Problems
Most vehicles have 2 axles one that connects the front wheels, and another that connects the rear wheels.
Vibration can occur if either of the axles is bent or dented which can happen in an accident or other mishap with the road and vibration will usually increase in intensity as you accelerate if the problem is related to the axle.
Also, inspect the CV joints and driveshaft for potential problems. If the CV joints are worn, that can let in dust and other debris which can damage the joints.
4. Worn Suspension Parts and joints
Looseness in suspension or steering system components can cause your steering wheel to shake. Excessively worn ball joints or tie rod ends make it impossible to properly align your vehicle.
Take your vehicle to a mechanic and have them inspect your ball joints and other components to help identify what is causing your steering wheel to shake. A car lifted at the shop. Mechanic working on suspension of the vehicle under the vehicle
5. Wheel Problems
If your steering wheel feels wiggly or wobbles when you drive, this can cause vibration problems as well and it may mean that one of the wheels is not spinning properly, or it may relate to the wheel bearings, tie rod ends, or ball joints.
Depending on the specific type of vibration the driver is feeling, the problem can be related to the tires and can be addressed in a number of ways. If vibration is felt at certain speeds, the tires may need to be balanced.
If the tires are wearing unevenly and causing the car to vibrate, the driver may need a tire rotation. In some cases, the driver may need new tires to solve the problem of vibration.
Why Is My Car Shaking When I Brake?
One of the more common reasons for your car shaking when you apply the brakes is due to substances gripping the rotor. When you press down on the brake pedal, a caliper applies pressure to the brake pad.
In turn, the brake pad pushes down on the rotors to stop the vehicle’s wheels from spinning. Over time, brake pads accumulate oil, dirt, or other materials. When this happens, the substances can cause vibrations, particularly when you press the brake pads.
Also, over time the rotors get thinner, making them susceptible to damage. During braking, excessive heat is generated and can cause the rotors to warp. This can also lead to slipping brake pads. To prevent this issue, make sure you have your brake rotors replaced around the 70,000-mile mark.
You might need to replace them earlier depending on your vehicle’s weight, your driving habits, and the climate where you live.
You might also notice a sharp noise coming from the outside of your vehicle when you apply the brakes. This noise could signal that your brake pads are worn.
If this occurs, replace your brake pads as soon as possible. You should check with your owner’s manual on when you should replace the brake pads, but you should typically replace them every 50,000 miles.
Why Is My Car Shaking When I Drive?
We’ve discussed your car shaking while braking, but what if your car shakes when your foot is nowhere near the brake pedal? If this sounds like your situation, you may have misaligned wheels or improperly balanced tires.
Typically, you can tell which of the two issues is to blame depending on where you feel the shaking. If the shakes come from the steering wheel, your car likely needs an alignment check and service. If they come from the floorboards and seats, a tire balance may be needed.
While wheel misalignment happens when suspension components are not properly angled, tire imbalance occurs when the weight of your car isn’t properly distributed on all four tires.
Such improper weight distribution can lead to excessive shaking, especially when you drive above 55 mph. To make matters worse, imbalanced tires can wear out prematurely, creating dangerous driving conditions that can only be remedied with entirely new tires.
Why Is My Car Shaking When I Stop?
If the vehicle shakes or the engine shudders a lot when stopped at a stoplight, or when parked with the engine idling, it might indicate the motor mounts or transmission mounts are damaged or broken. If the shaking decreases, it’s a strong indicator the engine’s motor mounts need to be inspected by a mechanic.
Why Is My Car Shaking When Idle?
Your car shakes every time you stop, but you definitely don’t live near an earthquake-prone area! While a shaky idling car can certainly feel like an earth-rumbling tremor, it can also indicate a problem with the engine.
One common cause of shaking while idling can be loose engine mounts. Engine mounts are the connections between your engine and your car they keep your motor safely attached while dampening vibrations produced by your engine. When those connections wear out, you’re more likely to feel the vibrations.
Alternatively, a car that shakes when idle may have faulty fuel injectors, worn-out spark plugs, or a bad timing belt. Some of these engine troubles can be corrected with a standard engine service or fuel system cleaning, but others may require more extensive engine repair.
Why Is My Car Shaking When I Accelerate?
Loose or damaged engine mounts may also be to blame if your car shakes when accelerating. As previously mentioned, damaged and loose engine mounts can’t efficiently absorb the vibrations produced by your cranking engine, so you’re likely to feel them when you step on the gas.
In some cases, a misaligned steering and suspension system could cause your steering wheel to shake when you accelerate. These two issues feel similar to you, the driver, but they have very different solutions.