If you’ve owned a car for quite a while now, it’s basically inevitable that you’ve experienced several auto-related problems along the way. One of these common culprits is car shaking while driving. Not only it is irritating, but this problem can also make you feel nervous especially if your car begins to wobble while speeding downhill.
Now, the best thing about car vibration issues is that they start early. If you’re an experienced motorist, you can easily read the symptoms and determine whether it’s serious enough to hire a mechanic or if it’s just a small issue that requires a simple fix. However, for average motorists, it can be challenging to identify the vibrations at an early stage as they always start off smoothly then creep up gradually to nuisance shakes.
With that said, whether the problem is a minor issue or something major out of the ordinary, this short guide will get deep into your car’s mechanical components to look at some of the common culprits that might cause your beloved auto to shake.
10 Reasons Your Car Shaking While Driving
1. Loose Lug Nuts
The first cause, which by the way, happens to be the most common is loose lug nuts or bolts (for the sake of some car models such as BMW). If you’re replacing your car’s tire while in a hurry, chances are, you’re likely to hand tighten the lug nuts and forget to perform the final tightening. Since the nuts are not properly tightened, the next thing you’ll experience is the tire wobbling and in some cases coming off.
Since you can’t wait for the latter, it’s strictly recommended that you drive your car off the road and inspect the lug nuts. If there are any loose nuts, then pick the lug wrench and tighten them back inside the hub. Now, apart from ordinary human error, two more reasons can cause loose lug nuts. The first is over-torquing the lug nuts beyond their resistance capacity. This can cause cross-threading or cracking of the nuts.
Another cause is an improper mating surface that includes clamping the nuts on a damaged/bent hub or a contaminated (rusty, dirty, corroded, or painted) mating surface. What happens is that the nuts will feel tight at first. However, as the rust, dust, and paint wear off, the nuts will eventually loosen.
2. Worn Out Braking System
If you happen to apply the brakes and you realize that your car is shaking, then you guessed it right—it’s a faulty braking system. In most cases, the main culprit is the front braking mechanism as it’s the one that shoulders all the stress when brakes are applied. Although there are so many components in the front braking mechanism, there are two main components that are usually involved here—the brake pads and the rotors.
The rotor is generally the rounded steel disk that attaches to the wheel. Although it’s made from heavy-gauge steel, this component can suffer from heavy wear due to friction caused by the brake pads when a braking force is applied. Now when you apply the brake, the brake caliper squeezes the brake pads against the rotor.
Following substantial use, these pads can thin and wear out causing scratches on the rotor. This scratching is what causes the vibration whenever you apply the brakes. Thankfully, most car models are fitted with longer-lasting braking mechanisms that can last for about 50,000 miles before they’re replaced.
3. Sticky Brake Calipers
Another reason that can cause your car to shake when driving is sticky brake calipers. Previously, we mentioned the main task of calipers is to press the brake pads towards the rotor to create a friction force that stops the car. Now, there are times when these brake calipers can become faulty and get stuck unexpectedly causing the steering to shake.
The good news, however, is that this problem can be identified easily by checking the speedometer to see in which speed range the shaking begins. In most cases, this happens when you reach a speed range of 40 – 50 mph. The problem is also likely to worsen the more you accelerate to higher speeds.
Now, since the vibrations are basically friction between the brake calipers, the pads, and the rotor, you’re likely to smell a burning odor.
4. Bent Axle
Another common cause of your car shaking or vibrating while driving issues with the axle. Most car models have two axles—one connected to the front wheels and the other to the rear wheels. Now, supposing you get involved in an accident or you hit a pothole accidentally when speeding. Then it means you’re most likely to damage the axle by bending or denting it.
This damage to the axle is the one responsible for the vibrations you experience and it’s likely to intensify as you accelerate your car. Now, there are times when the axle might not be the cause. In such a situation, you might be forced to inspect the driveshaft as it’s the one tasked to transfer engine power to the rear axle (especially in manual cars). If the driveshaft is damaged (bent), then it can cause vibrations as well.
Other components in this bracket that can also be the cause are constant velocity (CJ) joints. Now, these components have rubber boots that prevent lubricants from leaking out and prevent dust, water, and debris from the road from sneaking in. if they’re worn-out, then it means they can no longer prevent all sorts of debris from sneaking inside the CJ joints thus causing vibrations.
5. Erratic Motor Mounts
If you’ve ever peeped in your car’s hood, you might think that the engine is just wedged inside there without anything supporting it. However, in reality, the engine is usually secured on the car’s chassis by special mounts called motor or engine mounts. Now, these mounts are usually made of metal and hard rubber.
The metal part is responsible for providing structural integrity by offering a firm frame to bolt the engine. Once the engine is secure, the rubber part takes over by absorbing the various engine vibrations to provide you with smooth flawless drivability.
Now, with time, the rubber section of the motor mount is likely to thin and wear out. When it does, you’ll suddenly and gradually start to notice some shaking on your car which will intensify with time into disturbing vibrations. If this issue is not fixed on time, the engine can vibrate and get misaligned causing breakage to crucial components within it.
6. Engine Problem
Sometimes the problem might not be the tires or the braking system but rather the engine itself. As the heart of your car’s overall performance, the engine is the largest component that houses numerous complex mechanical parts. Some of these parts include the air intake filters and the spark plugs. Now, if any of these components malfunctions, then your car is likely to shake while driving.
Thankfully, vibrations caused by the engine are easy to identify as they come with unique symptoms that are easy to tell. These include:
- Your car shudder and jerk when you accelerate
- Staccato shaking when you reach a certain speed range
- The car feels okay at first then starts to shake later
If that’s the case, then it’s clear the problem is engine related. Here, the spark plug can be the main issue (more of this on our next point). The second problem can be clogged air intake filters. If these filters are clogged, then it means there’s a lack of sufficient oxygen getting to the combustion chamber. This will result in an inefficient fuel-air mixture which is likely to starve the engine and cause your car to shake.
7. Worn Out Spark Plugs
On our previous point, we mentioned about the engine being the cause of your car’s shaking. There, we mentioned a dirty air filter as being the main culprit. At this point, we will look at the second possible reason, which is a faulty spark plug. Now, just like other mechanical components, the spark plug too can wear out and become defective.
To prove this, there are some symptoms you’re likely to see such as:
- Increase in vibrations when you accelerate
- Feeling as if you’re driving on a constant stream of small bumps with the car still shaking
- Your car starts smoothly then begin to shake as it accelerates
- The check engine light appears out of nowhere while the car is still shaking
So, if you experience any of these symptoms, then it’s clear that your car’s spark plugs are worn out and need to be inspected. You see, the spark plug is responsible for transferring power from the ignition coil to the combustion chamber to ignite the air-fuel mixture to start the engine. Once it gets faulty, it simply means there’s inefficient power to run the engine leading to vibrations and finally loss of power.
Thankfully, repairing or replacing this component is quite easy. First, the kit is quite inexpensive in case it calls for a replacement and the overall repair work doesn’t cost much.
8. Damaged Tires
The absolute number one cause of your car shaking while driving issues to do with the tires. Remember, the tires are the only components in your car that are in direct contact with the road. This alone makes them susceptible to regular wear and tear more than any other component. Now, in case the vibrations are caused by the tires, many reasons can explain this some of which are listed below.
- First, most EVs and hybrid cars are fitted with low profile tires to reduce drag and resistance in a bid to improve the car’s EPA fuel economy rating. While that’s the future of modern cars, the drawback to these tires is that they have less material that prevents them from absorbing much of the road’s imperfections. This alone causes the car to shake especially if you’re not used to them.
- Another reason is when the tires wear out unevenly. This leads to an imbalance that causes vibrations.
- Modern tires are built with a new material that prevents them from bursting while driving. If this material (tire tread) is separated from the tires as they age, then they’re likely to cause vibrations.
There are other times when the problem might not be the tires exactly but rather the wheels that hold the tires. This can come in the form of loose or damaged wheel bearings which prevent the tires from rotating smoothly thus causing the shaking experience. Another explanation could be worn out ball joints or tie rod ends which too will need to be inspected and repaired.
9. Improper Tire Balance
Tire imbalance is another major issue that can cause your car to shake while driving. Two main possible reasons can explain this problem. First, if you’re having new tires, they’re likely to have different weights which might cause them to rotate differently. When this happens, tiny vibrations can be felt as you accelerate which are likely to either reduce or intensify.
The second is having old tires that tend to lose their balance differently as they age. Overall, whether the problem is caused by old or new tires, your car’s tires will require a comprehensive inspection.
10. Faulty Steering Components
The last possible explanation as to why your car shakes while driving issues with the steering components. When your car was brand new, the steering system was more responsive making the car more drivable and easy to handle. That’s because most of the steering components were new and young back then making the responses much quicker.
Now, as these components age, they begin to wear out slowly by slowly making it harder for you to manage the car while driving. If the damage to these components reaches a critical stage, then you’re likely to face steering problems which over time will cause vibrations and shaking of your car while driving.
5 Possible Solutions
Shaking on your rocking chair can be soothing and relaxing. However, having the same experience when driving is probably bad news. Although there are so many causes, like those discussed above, the good news is that there are possible solutions that can remedy each of these issues. With those few remarks, let’s look at five possible solutions that can fix this annoying problem.
1. Try Tire Replacement
Although we discussed tire issues at the end of our previous section, this is probably the very first cause of your car shaking. That’s because the tires are the ones in contact with the road. If the tires are worn out, you can consider replacing them with a new set. If they’re still young and the shaking problem persists, then you can try rotating them to see whether the issue can be solved.
Now, if the problem is caused by imbalanced tires, then you’ll have to use a jack, a lug wrench, and a flat end screwdriver to remove the wheel weights and the wheels to diagnose the problem with the help of a balancer. Since the process is quite complex, you’ll need to have your mechanic diagnose the problem on your behalf.
2. Spark Plug Fix
Now, if the problem is caused by the spark plugs, then the best remedy is to replace them with new ones. Sometimes the issue might be as small as dirty spark plugs where you’ll have to clean them then fit them back. Now, since spark plugs are quite delicate, failure to handle them properly when cleaning might lead to even more serious problems than before such as damage to the engine itself.
So, to avoid any of these uncertainties, it’s better to replace the spark plugs altogether. When doing so, you need to first locate the old one and take it off. Spark plugs are usually found under the engine’s plug covers. Once you remove them, you need to replace them with exactly the same spark plugs. Fit the new plugs on each hole and avoid overtightening to prevent damaging the engine’s head.
3. Have the Brake System Checked
Other than the spark plugs, we’ve seen that the braking system can also be the cause of vibration issues. We’ve discussed the brake pads, the rotor, and the brake calipers as being the main culprits here. So, to prevent these vibrations, not forgetting smelling burned rubber, you need to take your car to a mechanic for a comprehensive inspection.
Since the braking system is one of the most important components of your car, your mechanic will have to disassemble it all together to inspect the root cause. Here, the inspection process will check for corrosion on the disks, pads, and calipers, signs of breakage, and anything to do with regular wear and tear.
Depending on the condition, your mechanic might opt to repair the braking system by cleaning the various components then lubricate them thoroughly, or simply replace them with new ones to prevent any uncertainties in the future.
4. Low Transmission Fluid
Other than replacing a worn-out tire, another process that can easily be accomplished by almost any motorist, including novices, is adding transmission fluid into the transmission hole. Remember, this is another highly common cause of car vibrations when driving.
So, to accomplish this, you need to keep the engine idle by starting the car with the handbrake locked. When you’re done, read the instruction manual to know how much is enough depending on your engine’s specifications. Finally, add the fluid to the transmission to around halfway then start pouring small portions until the level gets to the maximum.
Now depress the brakes and run the transmission to circulate the fluid throughout the system. If everything sounds great, you may now put back the dipstick to the transmission hole to lock it back into place.
5. Replacing Damaged Motor Mounts
Just as we mentioned earlier, motor or engine mounts are responsible for holding the engine in place inside the chassis and absorbing vibrations to prevent them from being heard inside the car. Following regular use, these mounts can sometimes give up the run by wearing out. Some of the visible signs you’re likely to see here are leaking liquid (for those mounts that rely on liquids instead of rubber to absorb engine’s vibrations), cracks, wear, and sagging of the engine towards the faulty motor mount.
So, to replace the motor mounts, you need to first inspect the engine to ensure that you don’t end up damaging its components when you attempt to jerk it. Use a wooden block to support the engine when jerking it. Before you do so, first loosen the engine from the motor mount bolts. Crawl under the car and do the same for the bolts beneath.
Once the engine breaks free, jerk it to remove the faulty motor mount. Bolt the new mount towards the car’s frame then lower the engine to tighten the bolts.
And that’s it for today. As you can see, there are so many reasons that can cause your car to shake while driving. In fact, apart from the ten we’ve mentioned, there are other reasons that can cause this problem some of which are mild and others critical. Since you’re not certain what exactly the problem is, it’s always a good practice to visit a professional mechanic early enough to have your car checked.
For the case of mild issues such as tire wear, inefficient transmission fluid, and loose lug nuts, you can check these ones all by yourself to keep your car in good working order.