When you approach highway speeds – 60 mph and above – and your car begins to shake, it can be a terrifying experience. Fortunately, it’s more than likely a simple repair; however, you should get it inspected as soon as possible.
When your car shakes and vibrates every time you reach 50-70 mph, the majority of the time, it has something to do with your wheels and/or tires. The wheels are out of balance, the tires are unevenly worn/flat spots, incorrect tire pressures, or you may have a bent rim.
If your wheels and tires check out and are in working condition, you must dig deeper and inspect your brakes, suspension, steering, engine, and final drive components to pinpoint what’s to blame.
It’s important to note that the shaking and vibration, or its cause, may damage your vehicle the more you drive it. In the worst case, continuing to drive your car may result in an accident.
While the cause is most likely something simple, make sure to reduce your speeds and don’t make any unnecessary trips, and most importantly, get it inspected ASAP.
Should You Be Concerned if Your Car Shakes at High Speed?
You absolutely should be concerned if your car is shaking at high speed! It could be a sign of a serious issue such as worn tires, a broken belt in a tire, loose tie rod ends, or ball joints. It could also be a loose wheel bearing, in which total wheel bearing failure can result in the complete loss of a wheel at high speeds, and this is the last thing anybody wants.
As mentioned earlier, it’s more than likely something simple like out-of-balance wheels, worn tires, or uneven tire pressures. But you could have a tire blowout, sudden difficulty steering, or lose control of your steering completely, which could cause an accident and is 100% avoidable.
Top 10 Causes of Car Shaking When Going Over 60 MPH
There are several different causes of a car shaking when going over 60 mph. It’s important to identify the cause of the shaking in order to determine the best way to fix it. Here are some of the most common causes of the car shaking at high speeds:
1. An Imbalance in the Tires
Balancing your wheels is done after mounting new tires to the rims and should be done routinely. The assembled tire/rim mounts onto a computerized balancing machine, and weights are added to the rim accordingly. This ensures that your wheels spin smoothly and flawlessly at all speeds.
This can be visualized if you watch pool players check their cues for straightness; they roll them on the table and can see if they are bent. The computerized balancer does the same thing and allows technicians to add weights when needed.
However, your wheels can become unbalanced during operation by:
2. Worn Tire Treads/Uneven tire pressures
Another common cause of car shaking at high speeds – 60mph and above – is worn tire tread. Worn tire tread can cause the car to vibrate as they are no longer able to grip the road properly.
If you have uneven tire wear, this could be a sign of loose steering and/or suspension components or improper alignment. Specialized equipment is needed to check your alignment, so if you see signs of uneven or feathering or tire wear, contact your local repair shop.
Some other causes of shaking and vibrations due to tires:
If you have worn-out tire treads, meaning tread depth that is less than 3/32nd, it needs to be addressed as soon as possible. Pushing tires beyond their limits is a recipe for disaster.
3. The car has worn Brakes
Although unlikely, worn brakes can also cause a car to shake at high speeds. This is because the brakes are responsible for slowing the car down; if worn out, they may not be able to do their job properly. For example, if your brake rotor is out-or-round or warped, it may cause a vibration while braking at different speeds.
This should be pretty easy to pinpoint because the symptoms will only be felt during braking. There is a possibility that other failing brake components could cause a vibration such as a stuck brake caliper piston or a clogged flex line. However, these would be accompanied by other symptoms such as burning smells and steering pull when braking.
4. Check if the Wheel Bearing is Loose
A loose wheel bearing can also cause a car to shake at high speeds. This is because the wheel bearing is responsible for keeping the wheels in place, and if it is loose, it can cause the car to vibrate. In the worst case, you could completely lose your wheel while driving.
It may also cause a droning noise that increases with speed. To diagnose a loose wheel bearing, the car should be raised off the ground, and the wheel should be shaken and spun to see if there is any play in the bearing or obvious sounds. If so, the bearing should be replaced as soon as possible to prevent any further damage to the car.
5. Worn Steering and Suspension Components
Worn suspension components can also cause a car to shake at high speeds. Worn or broken strut mounts, shocks, and springs can cause the car to vibrate as they can no longer absorb the road’s impact properly.
Shock absorbers are meant to dampen any road imperfections and make things less bouncy, so if they are damaged or leaked out, they could cause a vibration above 60mph.
Additionally, worn tie rods and ball joints can also cause a car to shake as they can no longer keep the wheels aligned properly. Worn suspension components should be replaced as soon as possible to ensure the car’s stability and safety.
6. Engine Misfire
An engine misfire could be the cause of the car shaking at 60mph and is generally caused by a malfunction in the spark plugs, ignition coils, or other ignition system components. It could also be caused by a vacuum leak, clogged fuel injectors, or a faulty fuel pump. Generally, a misfire will be more pronounced when pressing the gas or going uphill.
Here is a general guide to pinpointing a misfire:
7. Worn Driveshaft Universal Joint
If you are experiencing intermittent vibrations, your universal joint may be the cause. The universal joint is responsible for connecting the drive shaft to the transmission and differential, and if the joint is worn out or out of alignment, it can cause vibrations.
Most times, if you have a driveline issue such as worn or seized u-joints or center bearings, the symptoms will be more pronounced “under load”, which means during acceleration or while going up hills.
To check your universal joints and driveshaft components, you will need to inspect it for any signs of wear and tear.
8. Check for Poor Alignment
Misalignment of the wheels can cause an uneven distribution of force on the tires and suspension components, leading to vibrations as the vehicle moves. Poor alignment can also cause excessive wear on the tires, which can also cause a vibration.
Here’s a checklist for checking your alignment:
Although possible, poor wheel alignment is most likely not the cause of your car’s vibration.
9. Engine or Transmission Mounts can cause the issue
Engine and transmission mounts are other possible causes of a vehicle vibrating at high speeds of over 60 mph. These mounts are responsible for keeping the engine and transmission in proper alignment.
If the rubber (or hydraulic fluid in some cases) is worn or missing, the geometry changes, and the power delivery will be uneven, causing vibrations and possibly noises as well.
To check your engine and transmission mounts,
If you find any signs of damage or wear, then you should replace the mounts immediately.
10. Worn or Out of Balance Axle
A bad axle can cause a vibration above 60mph by causing an imbalance in the wheel assembly. This imbalance can cause the wheel to wobble as it rotates, which results in a vibration that can be felt through the steering wheel and seat.
The vibration will be more pronounced as the speed of the car increases, as the wheel is spinning faster and doing more wobbling. If you can, jack your car up and grab the axle shaft to check for any play. In addition, if your car is making a clicking noise when turning, it is a good sign that your axle is defective.
If your car shakes when you hit 60 mph, it is essential to have it inspected and repaired immediately. There are several different causes of a car shaking at this speed, but as mentioned, the tires or wheels are most likely the culprit.
If your tires and wheels are good, and you’ve checked your brakes, suspension, steering, engine, and final drive components and came up empty-handed, you should seek professional help.
The mechanics can road-test your car and have a good idea of what’s going on. Although it may be nerve-racking, the problem should be fairly simple to solve and most likely won’t break the bank!
Jason Farrell is a certified master technician, the editor of Mechanic’s Diary in Pittsburgh, Pennsylvania. He is ASE (Automotive Service Excellence) certified and earned a Bachelor’s Degree in Automotive Technology from Pittsburg State University. With nearly 18 prior years of experience in the automotive field, he has extensive knowledge about Domestic, European, and other foreign makes and models of cars and light trucks. Jason’s experience working as a technician and service manager at dealerships, gave him the experience and know-how of most aspects of inspection, diagnosis, and repair from engine and drivability to electrical, HVAC, brakes, steering and suspension and everything in between.