Nothing’s more terrifying than cruising down the highway at 65mph when suddenly your car starts shaking like it’s having a seizure. Your heart drops as you grip the wheel trying to maintain control while safely pulling over. “What the heck is going on?!” you think.
A car vibrating violently at high speeds is no joke. It’s downright dangerous and makes driving feel like trying to steer a mechanical bull. But take a deep breath – in most cases, a shaky ride is fixable.
This comprehensive guide will walk you through all the potential reasons a car shakes when going 60mph or faster. We’ll also provide tips to diagnose the root cause and explain how to smooth out your ride. Buckle up and hold on as we get to the bottom of high-speed vibration.
Table of Contents
Why Do Cars Shake at High Speeds?
Many components and systems work together to give a smooth, stable ride. When one part wears out or falls out of balance, the harmony is disrupted. Suddenly 60mph feels like warp speed.
While scary, shaking and vibration at highway speeds usually boils down to a few key culprits:
The most obvious place to start is those four circles of rubber meeting the road. When tire weight distribution is off, steering wheel shake and vibration result.
Out-of-round tires, uneven tread wear, and lack of balance are common tire issues leading to shake. Low tire pressure can also contribute by changing weight distribution.
Your suspension system works to absorb impacts from the road and keep tires firmly planted. When parts like struts, shocks, ball joints and control arms are worn, you lose stability. The looseness translates to bounce and shake at speed.
Wheel Alignment Issues
Incorrect alignment causes tires to drag and bounce rather than roll smoothly. This dynamic gets exponentially worse with speed.
Issues with motor or transmission mounts, u-joints, axles, and driveline balancing can send violent vibrations through the chassis at higher RPMs.
If you feel shaking under braking at highway speeds, contaminated brake rotors are likely the cause. Sediment buildup on rotors can create pulsation and vibration.
Now let’s explore these common culprits in more detail and learn how to get your ride smooth again.
Unbalanced tires are the number one cause of cars shaking, vibrating, and feeling “squirrelly” at 60mph plus.
When a tire’s weight distribution is off, heavier sections create momentum that’s compounded by speed. Suddenly you feel like you’re riding a mechanical bull.
Getting your wheels balanced correctly aligns the tires’ rotational mass and creates smooth, even rolling.
Signs of an Unbalanced Tire
- Steering wheel and/or seat shaking, especially between 55-75mph
- Vibration getting worse with increased speed
- Tire thumping or hopping sensation
How to Fix Unbalanced Tires
While you can try repositioning tires yourself, the best fix is getting a professional wheel balancing.
Tire techs have machines that spin the wheel and detect heavy spots. They use weights to counterbalance those sections for smooth rolling.
Cost is usually $15-30 per wheel. It’s smart preventive maintenance every 5,000-7,000 miles.
Balancing won’t help if tires have underlying issues like being out-of-round. In that case, new rubber is required.
Out of Round Tires
Tires get worn down with age and lose their perfectly round shape. This “out-of-round” condition causes bouncing at speed.
Tires may become unevenly worn due to bad suspension parts, lack of rotation, or improper alignment. The tread loses uniformity, creating vibration.
Signs of Out of Round Tires
- Bounce or steady vibration, especially at certain speeds
- Sawtooth wear pattern on tread
- Visibly abnormal tire shape
How to Fix Out of Round Tires
Unfortunately when tires get significantly out of round, the only remedy is replacement.
First address any underlying issues like bad shocks or improper alignment that caused uneven wear.
Rotate tires regularly to encourage more even distribution of wear.
Closely monitor tread depth and wear patterns with routine inspections. Replace when abnormal wear is detected.
Wheel Alignment Issues
Wheel alignment keeps tires rolling straight and true rather than scrubbing and dragging.
With improper alignment, tires sit at awkward angles and have to overcome drag to roll. This resistance intensifies vibration and shake the faster you drive.
Signs of Bad Alignment
- Vehicle pulling to one side
- Steering wheel off center when driving straight
- Uneven tire treadwear
How to Fix Alignment Issues
Regular alignments compensate for suspension settling that knocks things out of spec over time.
Alignment involves adjusting camber, caster, and toe settings to manufacturer recommendations.
Cost ranges $50-150 and should be done anytime you notice alignment symptoms or uneven tire wear.
Address any worn suspension parts that may be preventing proper alignment.
Worn Out Suspension Parts
Your suspension system is a finely tuned network of components designed to absorb impacts and keep tires firmly planted on the road.
When parts wear out, handling suffers. Excess play in the system allows tires to bounce leading to vibrations and instability at speed.
Common Suspension Issues Causing Vibration
- Shocks/Struts – Worn out struts allow bouncing after bumps. This resonates through the chassis.
- Ball Joints – Excess play in worn ball joints introduces steering wobble.
- Control Arms – Damaged or loose control arms alter wheel angles causingscrubbing.
- ** Springs/Coils** – Weak or broken springs hurt responsiveness and shock absorption.
How to Fix Suspension Issues
Fixing your suspension starts with a thorough inspection to detect loose, damaged, or worn parts.
Replace any components that are deteriorated. Tighten or replace loose fasteners.
For optimal handling and ride quality, replace shocks/struts every 50,000 miles.
Loose Lug Nuts
Don’t underestimate the importance of properly torqued lug nuts. They keep the wheels securely attached to the vehicle.
When lug nuts loosen up, it allows wheels to wobble and shake. This dangerous condition intensifies with speed.
Causes of Loose Lug Nuts
- Improper tightening
- Not torquing with a calibrated wrench
- Damaged studs or lug threads
- Wheels installed incorrectly
How to Fix Loose Lug Nuts
ALWAYS use a torque wrench to tighten lug nuts to spec – never just muscle them down with an impact gun.
Replace any damaged studs or lugs. Check wheel hub/rotor for damage if studs are broken.
Retorque lug nuts after 50-100 miles to ensure they stayed tight.
Check torque spec every tire rotation or oil change. Tighten if needed.
Other Potential Causes of High Speed Shaking
Beyond the most common tire and suspension culprits, sometimes more complex drivetrain or brake issues are the root of your high speed vibration.
The engine and transmission are precisely balanced rotating assemblies. Issues in those systems can cause shake and vibration, especially at higher RPMs.
Potential Drivetrain Issues:
- Bad motor or transmission mounts – Allow too much movement under power
- Bent drive shaft – Throws off rotating balance
- Unbalanced prop shaft – Heavy spots create vibration
- Misaligned U-joints – Bind and cause harshness during power delivery
- Bad CV joints – Excess play leads to instability at speed
If vibration happens primarily under acceleration, have your mechanic inspect the driveline. Hard shaking when shifting gears can also indicate drivetrain problems.
Issues in the braking system often emerge as shaking or pulsation in the pedal. Problems get amplified when braking at highway speeds.
Potential Brake Issues:
- Contaminated brake rotors – Sediment buildup causes thickness variation and pulsation
- Uneven pad deposits on rotors – Creates thickness variation leading to vibration
- Caliper issues – Dragging or sticking caliper also creates pedal pulsation
- Excess rotor runout – Causes pedal pulsation under braking
If your vehicle only shakes when braking at high speeds, focus on inspecting the brake system. Resurfacing or replacing rotors will often smooth things out.
How to Diagnose the Cause?
Tracking down the root cause of high speed vibration requires a process of elimination. Here are some tips:
Pay Attention to When It Happens
Note if shaking is constant or only under certain conditions like acceleration or braking. This helps indicate affected system.
Where Do You Feel the Shake?
General chassis vibration likely points to tires/suspension. Shake through steering wheel or seat suggests front end.
Test Drive with a Shop
Experienced techs can often isolate the culprit by road testing with you. Their diagnostic skills pinpoint the issue.
Move the front tires to the rear and vice versa. If vibration follows the tires, you’ve identified the problem area.
Look for Clues
Inspect for things like uneven tire wear that indicate alignment or suspension issues. Look for leaking shocks or damaged components.
Sometimes multiple factors contribute to vibration. You may need to correct several issues to fully smooth out your ride.
Address any underlying problems first, then move on to fine tuning things like wheel balance for long-lasting results.
How to Stop Your Car From Shaking at High Speeds
Now that you know what causes shaking and how to diagnose it, here are some best practices to stop vibration and improve high speed stability:
Get Regular Alignments
Keeping your wheels properly aligned reduces uneven tire wear and improves rolling resistance to mitigate vibration at speed.
Rotate Tires Frequently
Regular rotations help distribute wear more evenly across your tires for better balance and roundness.
Balance Tires Every Oil Change
Routine balancing counters normal weight shifts and maintains smooth rolling performance.
Inspect Tire Wear
Look for abnormal patterns like choppy shoulder wear that indicates bad alignment or suspension parts.
Tired dampers allow bouncing that leads to vibration. Follow recommended replacement intervals.
Torque Lug Nuts Properly
ALWAYS use a calibrated torque wrench to tighten lug nuts. Loose wheels = shake.
Address Issues Immediately
Don’t ignore new vibrations. Identify the cause early before it creates additional problems.
Consider Premium Tires
Upgrading to top tire models optimizes characteristics like uniformity and high speed capability.
Restore confidence in your ride with these proactive maintenance tips. Investing in timely repairs pays dividends in performance and safety.
Cruise Smoothly Ever After
Few sensations compare to the pucker factor of an unstable car shaking its way down the highway. It’s like trying to steer a rocket-powered roller skate.
Thankfully a vibrating car is rarely a death sentence. In most cases, it’s an easy fix once the root cause is identified.
Follow the guidance in this article to smoothly diagnose and correct high speed vibration issues. With balanced tires, dialed alignment, and sound suspension parts, you’ll be cruising comfortably again in no time.
Now clear your schedule, grab some snacks, and hit the open highway to enjoy that buttery smooth ride with confidence. Just try not to glance down in horror when you realize you’re going 90mph. Happy motoring!