A vehicle that shakes can be unsettling for any driver. Some symptoms are so subtle that they only become noticeable at speeds higher than 70 mph. Unlike most wear-and-tear car problems, vibration issues can happen to both old and new vehicles and may not necessarily be due to negligence or overuse.
Typically, shaking and wobbling come from the steering wheel or brake pedal and progress over time if left unattended. Worn out parts and dysfunctional air-fuel mechanisms are also common culprits. Whichever the cause, it is best to resolve the issue early on before it gets worse.
Here are 20 common reasons why a car shakes when driving over 70 mph:
- Out-of-balance tires
- Misaligned wheels
- Uneven tire wear
- Wheel runout
- Faulty brake system
- Worn parts
- Low tire pressure
- Resonance in the exhaust
- Starved engine
- Overworked powertrain
- Shabby suspension components
- Bad CV joints
- Excessive lifts
- Failed spark plugs or spark plug wires
- Disconnected air or vacuum hose
- Incorrect gasoline Octane
- Engine sludge
- Rough driving
- Poor workmanship
- Make of the vehicle
This article will cover many of the common reasons for vibration in the entire vehicle and its different components. Likewise, you will discover that some of these causes indicate a power loss or a haphazard service.
This list should give you a comprehensive rundown of what to consider when determining why your car shakes when driving over 70 mph.
Car Shakes When Driving Over 70 mph
1. Out-of-Balance Tires
Imbalanced tires cause a vehicle to vibrate at higher speeds (within the 50–70mph range) and have a cupped or scalloped wear pattern. These tires usually have one section that is heavier than the other.
Hitting potholes, bridge expansion joints, and curbs result in out-of-balance tires, which could knock off a wheel weight, cause a sidewall bubble, or dent a rim. The tire’s damage then results in vibration in the steering wheel and through the seat and floor.
Vibration felt in the steering wheel would indicate impacted front tires, while vibration through the seat or floor would point to back tires. Avoid balancing the tires at home. This process requires using a computerized wheel balancer to measure the imbalance and determine the additional weights needed to correct the problem.
2. Misaligned Wheels
Another top reason a car shakes when driving over 70 mph is misaligned wheels, which could happen from hitting a pothole, for example.
Wheel alignment, which involves the angle at which wheels hit the road, would resolve this issue. However, certain conditions would indicate a need for a wheel alignment outside of shaking problems and regular maintenance, as follows:
- Uneven, severe, or rapid tire wear
- The steering wheel tilts to one side when driving straight
- Noisy steering
- Consistent pulling to the right or left
- Screeching tires
- After tire replacement
- After an accident or chance off-road trip
Having your car undergo an alignment inspection immediately following any of the above conditions increases the non-occurrence of vibration issues.
Depending on your car’s make and model, it may require a four-wheel or a front-wheel alignment (inclusive of setting the camber, toe, and caster). A professional mechanic will be able to align your wheels using a wheel alignment machine.
3. Uneven Tire Wear
A broken or slipped belt can cause your tires to vibrate or bounce, which means uneven wear on your tires. Having a new vehicle does not make you safe from this problem, as poor-quality tires are likely to wear out sooner (even when brand-new).
To determine which tire needs replacement, drive in the shake speeds, and feel for the vibration source. If more of the steering wheel shakes when driving, you may need to replace both front tires.
If you feel the rattling more from the seat or floor, you need to change both rear tires. In worse scenarios, you may need to replace all your rubber.
4. Wheel Runout
By definition, a wheel runout refers to any component of a wheel or tire assembly that is not perfectly round. It is a dynamic imbalance problem that results in wobbling at slow speeds and severe rattling at high speeds.
A flawed tire-wheel assembly may include tires with shifted or broken belts. Use a tire runout gauge (view on Amazon), off-car balancer, or dial indicator to check for radial and lateral runout.
The center of a tire tread is where you check for the radial runout, while the center of the tire sidewall is where you check for the lateral runout. Make sure that you do this on a smooth rib for the best results.
5. Faulty Brake System
Your brake pads and calipers may not get enough grip, leading to warped brake discs over time. Vibration through the steering wheel due to sticky brake calipers and rotors become noticeable starting at 45 to 50 mph.
The shaking gets worse the further you close into 70 mph, accompanied by a burning odor when you stop your vehicle. Wheel shaking caused by an issue with the front brakes will be more noticeable when braking.
When the rear brakes are the problem, you will feel the vibration in the brake pedal. To fix, either re-index the rotor one or two lug positions on the hub, get the brake parts machined, or replace them if severely worn down.
6. Worn Parts
Other parts of your car can wear out over time and cause vibration. These are shocks, upper strut bearings, ball joints, and tie rod ends.
Wear in these parts is usually discovered during wheel alignment and would need to be replaced to rectify the problem. Worn wheel bearings, for one, are easy to pinpoint as they make high-pitched whining or grinding noises. Wearing of tie rod ends causes your car’s wheels to oscillate.
7. Low Tire Pressure
In addition to poor fuel mileage, blowouts, and abnormal tire wear, low tire pressure can also cause car shake. A great way to maintain your tire pressure is to always have a tire pressure gauge and inflator with you.
Raising the tire pressure about 3 psi above manufacturer recommendation in cold weather will help mitigate tire pressure drop and keep it within the normal range.
8. Resonance in the Exhaust
Resonance may occur following a change in a vehicle’s exhaust system (changing the stock muffler or tailpipe with a different design) or a bent or incorrectly fitted pipe. However, it may be confused with wheel vibration.
Given certain speeds, the natural fluctuations occurring in the exhaust may stack up and create a buzz or resonance. Similarly, tuning weights typically attached to some vehicles to dampen chassis and drivetrain vibrations, when removed, may result in a car shake.
9. Starved Engine
For a car to run smoothly, its engine needs to get enough oxygen, fuel, and spark. Otherwise, jerks and shaking will happen when your vehicle increases speed or rumbles within a specific speed range.
You will also notice vibration coming from the engine compartment. Inspecting the spark plugs and installing a new set when needed will let you get a hold of the problem.
Additionally, ensuring that the fuel and air filters are not clogged or dirty and changing them regularly will guarantee that the engine is never deprived of the fuel or oxygen it needs.
10. Overworked Powertrain
An overworked powertrain usually causes a clicking noise while turning. A bad CV axle shaft may cause your car to shake while braking.
Excessive wear and abuse of your clutch, flywheel, gearbox, and steering rack components likewise result in shaking. The latter can be quite tricky, as the steering wheel shakes when driving only at 70 mph or more speeds.
11. Shabby Suspension Components
Typically, vibrations happen within the range of 50 to 75 mph. But if the shaking starts at a certain speed and gets worse by the minute, then worn differential and suspension mounts could be the likely cause.
Depending on the damage or what you have in your car, it may sometimes be more economical to have your vehicle replaced altogether than to have the entire suspension system rebuilt or replaced.
12. Bad CV Joints
CV joints can be hard to diagnose, especially in a rear-wheel vehicle. Problems with inner CV joints will usually occur under hard acceleration and heavy load. Depending on how bad it is, it could manifest as a minor vibration or violent shaking.
So, if your car shakes when driving over 70 mph and your tires check out, then you might have worn CV joints or a worse powertrain problem. If you experience shaking starting at speeds from 40 to 55 mph, check if your front axles are shot.
13. Excessive Lifts
An excessive driveshaft angle can also cause cyclic vibrations and is usually an outcome of raising or lowering the vehicle’s stock ride height by more than several inches – like 4×4 trucks that have been raised too much with a lift kit.
When a U-joint is at an angle, the joint’s out-of-norm geometry induces vibrations in the shaft. This means that the greater the angle, the stronger the vibration intensity.
14. Failed Spark Plugs or Spark Plug Wires
Dirty or fouled-up spark plugs cause the engine’s internal pressure to drop, resulting in power loss and leaving the remaining cylinders to compensate. In turn, this causes vibration or possible violent shaking.
You will first notice a slight bounce or repeated dip in the RPM needle when the vehicle is at a stop. Eventually, you will feel vibrations while driving.
You can catch a failing spark plug wire early on if your car has an RPM gauge. Similarly, one spark plug showing a dark buildup on the tip is a good indicator that the other spark plugs are bad as well.
15. Disconnected Air or Vacuum Hose
When air or vacuum hoses come loose, rupture, or begin to leak, air, fuel, and spark come out of proper proportion to the engine. When this happens, the lack of air pressure causes sensors to get confused, causing your car’s engine to lose power, misfire, run erratically, or vibrate.
That said, your air filter and fuel filter need to be in check as they play a vital role in power delivery. Replacing air filters is cheap and easy to do and should be done periodically.
However, it could be a different case for fuel filters (especially for vehicles with fuel injection), which may require servicing if located under the high-pressure line under the car and not under the hood.
16. Incorrect Gasoline Octane
Using fuel variants with a higher-Octane rating than what the manufacturer recommends may contribute to fuel efficiency and cleaner emissions but may be detrimental to your vehicle. Higher-Octane gasoline burns slower than its lower-Octane counterpart.
If your engine is rated for gasoline with an Octane rating of 87, stick to it. Otherwise, your engine’s inability to correctly burn the fuel will result in reduced power, higher fuel consumption, and potential engine shaking.
17. Engine Sludge
When engine oil deposits accumulate, they form a thick, almost irremovable sludge that can lead to power loss, expensive repairs, and shaking.
In like manner, when the oil level gets too low, the engine does not get proper lubrication. It may begin to vibrate before it loses power, overheats, or completely fails. Change your oil at proper intervals specific to your vehicle’s make and model to avoid this situation.
18. Rough Driving
Most drivers hate to admit it, but they have been guilty of roughing up their vehicles one way or another. Going faster than you are comfortable driving, getting in over your skills and abilities, or being rough with the steering wheel or throttle inputs is easier done than prevented.
Pair this with rough riding conditions, and you are sure to curb your vehicle or run over something hard on the road, resulting in steering wheel vibrations due to a damaged wheel or tire.
19. Poor Workmanship
There are occasions when vehicle owners experience their car shake after getting it serviced – usually after a tire replacement, wheel alignment, or a throttle body sensor calibration.
While blaming others should be last on anyone’s list, poor servicing is not an impossibility. If the vibration does not cease after everything sorts out, then it may be high time to bring your car back to the mechanic to have them recheck their workmanship.
20. Make of the Vehicle
Sometimes, it is nobody’s fault that your steering wheel shakes when driving. The rattling and shaking you are experiencing could be due to a missing body piece, the weight of your car (it might be super light), its aerodynamics causing resonance, or the draft coming off of surrounding vehicles on the road.
Or it could be that your vehicle is just not built for high speeds. Poorly fit accessories, or body panels may also cause rattling.
Things to Keep in Mind
Below are more things you can do to better deal with vehicle vibrations and to avoid wrestling with your steering wheel in the middle of the freeway:
Tires
Purchase good-quality tires and make sure to carefully inspect them when your wheeler goes in for preventive maintenance. When replacing tires, make sure to take your car out for a quick test drive immediately after to ensure that the new tires are not out of round.
Brakes
Including brake caliper service and inspection of brake pads during scheduled maintenance are especially important for vehicles with over 75,000 miles under their belt.
For cars with low mileage, brake service and inspection occur during the 6th-month vehicle checkup. Also, do not mistake a pounding brake for a tire vibration.
Patterns
If your steering wheel shakes when driving at highway speeds, then the possibility is a warped rotor. If you have a front-wheel-drive car and feel that its whole front end is shaking, perhaps one of the inner CV joints has an issue.
If the shaking happens only when you are lane changing at 70 mph or above speeds, consider checking wheel bearings. If the vibration occurs only when you step on the gas, then a worn tie rod, ball joint, manifold gasket leak, or inner CV joints could be the culprit.
Tools
Having an OBD/OBD II Diagnostic Scanner (view on Amazon) and paying immediate attention to engine warning lights are effective preventive measures. A decent, $25 OBD scanner will allow you to diagnose many issues and keep you from spending hundreds of dollars for repairs you could have done yourself.
Conclusion – Car Shakes when Driving over 70 mph
To summarize, here are the most common reasons a car shakes when driving over 70 mph:
- Out-of-balance tires
- Misaligned wheels
- Uneven tire wear
- Wheel runout
- Faulty brake system
- Worn parts
- Low tire pressure
- Resonance in the exhaust
- Starved engine
- Overworked powertrain
- Shabby suspension components
- Bad CV joints
- Excessive lifts
- Failed spark plugs or spark plug wires
- Disconnected air or vacuum hose
- Incorrect gasoline Octane
- Engine sludge
- Rough driving
- Poor workmanship
- Make of the vehicle
A simple visit to the mechanic right after detecting oscillations will help prevent other mechanical failure and expensive repairs. Additionally, regular maintenance, careful driving, and following manufacturer recommendations can prevent steering wheel vibrations.
Kris is an avid off-roader and outdoor enthusiast who loves to brave the elements and take on challenging terrain. He also enjoys sharing his passion and knowledge with others so that they, too, can appreciate the ride.
About Kris