If you are like most people and spend a lot of time in your vehicle, when something doesn’t feel right, it can be enough to drive you crazy.
If your car vibrates while idling, braking, or accelerating, it signals something is wrong.
What causes a car to shake when driving?
Some of the most common causes stem from worn or damaged wheels, tires, or brakes. There’s also the chance that something under the hood is the culprit, which suggests bad spark plugs, broken motor mounts, or a clogged filter.
Another possibility is that you have a bent axle.
Your best bet is to resolve any shaking issues before they worsen.
Thankfully, we will cover the 5 most common reasons a car might vibrate in this short guide. This will allow you to take the proper course of action should they show up.
Let’s get started.
Why Is My Car Shaking? Here Are 5 Common Reasons
Your Tires Are Worn
The average driver racks up between 12,000 to 15,000 miles each year. If you are running with a typical set of all-season tires, then you’ll likely have to replace them every 3-4 years to ensure they don’t become bald.
Thankfully, most tires feature built-in wear bars, which are rubber strips that sit in between the main tread grooves. If your tread wears down to the point that it’s flush with these, then it’s time to replace your tires.
But even if you drive less, you still have to worry about the tires themselves becoming old and drying out. This is known as dry rot, which causes them to become brittle, lose color, and start to crack.
A few things that can lead to dry rot include:
- Sitting for long periods without use
- High/low temperatures
- Excessive exposure to direct sunlight
- Exposure to corrosive or abrasive materials
Worn tires, or those with dry rot, can easily cause your car to shake while driving, in which case you should replace them right away. Otherwise, you are putting yourself and those around in danger by continuing to drive on them.
The Brakes Need Servicing
If you notice a vibration when braking, there’s a good chance there’s an issue in your braking system. Most notably, the rotors, which are circular discs attached to each wheel that spin with them.
Fixed over the rotor, is a brake caliper, which squeezes the brake pads against it, creating friction and slowing the rotation. Over time, the rotor can become bent or warped. When this happens, and the calipers squeeze against them, you may notice a vibration.
Thankfully, rotors last a while, usually between 30,000 to 70,000 miles. Replacing a rotor ranges from about $400 to as much as $550, depending on the make and model of your car. You may also be able to simply repair them, which runs for around $200.
Basically, any issue that involves your brakes should not be ignored. Warped rotors can not only reduce braking performance, but they can also make it hard to control your car in an emergency situation.
You May Have Engine Issues
There are several components under the hood of your car that can cause it to vibrate while idling or accelerating.
The first is bad spark plugs, which are in charge of igniting the air/fuel mixture inside each combustion chamber. If any of them are worn, it can interfere with them firing correctly. When an engine misfires, it can cause a shake with each cycle.
A shake doesn’t explicitly suggest faulty spark plugs, since, before air or fuel reach them, they each pass through their own filter. If your air filter or fuel filter is clogged, the spark plugs won’t receive enough of either to function. This can also cause a misfire, and thus a shake.
You might also have worn motor mounts. If you didn’t know, the engine is secured directly to the chassis of your car by (you guessed it) motor mounts. Thankfully, they usually last for between 5-7 years. Beyond this, they may weaken, which might lead to a noticeable vibration.
The good news is that spark plugs and fuel or air filters are cheap to replace. Motor mounts, on the other hand, range from about $200 to nearly $600.
Wheels Are Damaged Or Need Balancing
If your car shakes while driving, it may just mean you need your wheels balanced. Balancing is the process of distributing weight evenly across the tire and wheel assembly. This ensures that they rotate correctly at higher speeds.
Even a small weight difference from one wheel to the next can cause your car to shake.
Thankfully, most shops only charge between $15 to $45 to balance your wheels. They place it on a machine that spins it at a high rate of speed and then measure the weight around the circumference. The tech will then attach weights around the wheel to ensure it is perfectly balanced.
Damage to your wheels can also cause your car to vibrate. This usually stems from running over an object or a pothole. Thankfully, unless the damage is severe, a shop should be able to restore it to its original shape.
A Bent Axle May Be At Fault
If your car started shaking after an accident, or some other mishap like running over a large pothole or hitting a curb, you might have bent an axle.
If you didn’t know, an axle delivers power directly from the transmission to the wheel. It’s basically a shaft connecting these two parts, that rotates with the wheels. If you do have a bent axle, you’ll usually notice the shaking intensifies as you accelerate.
Repairing or replacing an axle can be costly, from as low as $170 to as much as $900. It all depends on the extent of the damage and whether a repair is even possible. The make and model of your car also influence the cost.
If it’s more than a shake, you might want to stop driving altogether until it’s fixed. Otherwise, you may wreak havoc on the rest of your suspension system, which can become expensive rather quickly. If the shake is minor, you should be ok driving for at least a little while.
Cars Don’t Shake For Fun
If your car is shaking or shuddering while driving, it signals there’s an issue. Ignoring it will most certainly ensure it worsens, which typically translates to a higher shop bill.
When was the last time you replaced your tires, spark plugs, or filters? How about balancing your wheels? Have you recently run over a large pothole? If it’s been a while, then a shake indicates it’s time to give it some attention.