Why Does My Car Shake When Braking? Common Causes & Fixes
Reviewed by Eric Shepherd, ASE-Certified Technician
Picture this: you're driving around Phoenix metro hitting all your favorite places. You approach a stoplight at an intersection and apply the brakes. Instead of a nice, smooth stop, the steering wheel starts shaking or you feel a pulse through the brake pedal. If you notice that your car shakes when coming to a stop, it means that something is interfering with the smooth application of the braking force. Your brakes aren't always to blame right away. Sometimes this can happen because of worn suspension components, wheel bearings or tires. Even lug nuts that haven't been properly torqued can contribute to vibrations when braking.
Where you feel the shaking, when it occurs and how severe it is can offer valuable insight into what's going on with your vehicle. For example, a steering wheel vibration when braking can point technicians in a different direction than a pulsating brake pedal might.
That said, brake vibrations are never something that should be ignored. Some causes can be super simple fixes while others can affect your ability to safely stop the vehicle.
Is the Vibration in the Steering Wheel, Brake Pedal, or Entire Vehicle?
Everyone likes to assume that any shaking in your vehicle is due to warped brake rotors, but at Gemba Automotive our ASE-certified techs will use the location of the shaking as well as the conditions it occurs in to better understand and diagnose the issue.
| Symptom | Most Likely Cause |
|---|---|
| Steering wheel shakes | Front brake rotors, suspension or wheel bearings |
| Brake pedal pulses | Rotor thickness variation or warped rotors |
| Entire vehicle shakes | Rear brakes, tires or suspension |
| Shakes mainly when braking at highway speeds | Rotor runout/thickness variation or brake heat issues |
| Shakes at highway speeds even without braking | Wheel/tire imbalance or a tire or wheel problem |
| Shakes only during hard braking | Brake overheating or a sticking caliper |
If you notice that the steering wheel shakes when stopping, it could be due to an issue somewhere at the front of the vehicle. On the other hand, if the pedal vibrates when braking, it could be due to inconsistencies between the brake pads and rotor surfaces. Alternatively, if you feel vibrations throughout the seat or body of the vehicle, it could point to things like the tires, suspension or the rear brakes.
Most Common Reasons Your Car Shakes When Braking
Warped Brake Rotors
The number one thing that comes to mind when your vehicle starts shaking while braking is warped rotors. Brake rotors, the large metal discs behind your wheels that the brake caliper clamps onto, experience tremendous heat when the brake pads are clamped onto them to stop the vehicle. The vehicle's motion causes the rotors to heat up. Under certain conditions, rotors can develop excessive runout, disc thickness variation or uneven friction-material deposits that cause braking force to vary as the wheel rotates. Drivers commonly describe this condition as "warped rotors."
The rotors usually won't appear visibly distorted. Instead, these irregularities create changes in brake force as the rotor turns, producing the pulsation or shaking you feel while stopping.
Uneven Brake Pad Deposits
During normal braking, a thin transfer layer of friction material can develop on the rotor surface. If that material becomes unevenly distributed, braking force can vary as the rotor turns, creating pulsation or vibration. Using your brakes all day, every day, it's easy to see how buildup can turn into deposits. Usually this occurs when there is repeated slamming on the brakes or the pads are wearing down unevenly. If the pads encounter areas where the surface is different, it can produce a vibration.
Worn Brake Pads
Brake pads don't always wear down evenly. Sometimes a caliper that is sticking or damaged can cause one pad to wear down faster than the other. As the friction material that makes up the brake pad becomes thin and uneven, it can lead to brake vibrations.
If you notice any squealing, scraping or grinding accompanying the vibrations you're experiencing, you will want to give the issue immediate attention. Grinding noises can indicate the pad material is gone and the backing plate may be making metal-on-metal contact with the rotor, which potentially reduces braking performance and increases repair costs.
Sticking Brake Calipers
Your brake calipers apply the brake pads to the rotors. If a caliper piston sticks, then the brake might not release itself or apply itself as it should. If the caliper sticks, it could create uneven braking force that will cause the vehicle to pull to one side and generate heat. Other symptoms to look out for include burning smells or one wheel seeming warmer than the others after driving. Continued overheating can damage the pads and rotors, turning a caliper issue into a large brake repair.
Loose or Worn Suspension Components
Sometimes the brakes can expose a problem, rather than cause it. For example, when you apply the brakes, all of the weight transfers toward the front of the vehicle and places additional loads on the steering and suspension components. Worn ball joints, tie rods or steering linkage can move and cause the shaking sensation when under load.
Wheel Bearings
Worn wheel bearings can also cause vibrations when stopping the vehicle. Other symptoms can include humming noises and grinding noises that change with your rate of speed or while turning. A worn wheel bearing is a safety concern as it helps support the wheel and hub assembly. If you suspect this is the cause, you will want to have it looked at promptly.
Wheel or Tire Problems
Damaged tires and bent wheels can throw off your wheel balance. If the wheel is out of balance, it can cause you to feel vibrations. The shaking might already exist at highway speeds, but it may become more noticeable as weight transfers forward during braking.
Why Does My Car Shake When Braking at High Speeds?
If your car shakes primarily when braking at highway speeds, excessive rotor runout or thickness variation is one possible cause, although wheel, tire, suspension and other brake problems can produce similar symptoms. Let's say you're driving along the SR-51 and you notice that your car vibrates when braking at high speeds but feels normal when you are driving around town. In this case, the higher speed might be making the problem more noticeable.
When you are traveling at highway speeds, everything is rotating faster, so any vibrations will become more pronounced. The heat generation during a high-speed stop can also further exaggerate the problem.
Wheel and tire issues also become more noticeable at higher speeds, especially when the weight transfers forward from applying the brakes.
Is It Safe to Drive If Your Car Shakes When Braking?
Braking is a critical safety system, so depending on the severity and cause of the vibration, it can affect the drivability of your car.
| Safety Level | What You May Notice | What to Do |
|---|---|---|
| Usually Safe Temporarily | Mild brake pulsation, normal braking performance, no pulling, no unusual noises and no warning lights | Drive cautiously until the vehicle can be inspected. Avoid unnecessary high-speed or hard braking. |
| Schedule Service Soon | Increasing vibration, noticeable steering wheel shake, inconsistent braking, squealing, scraping or other unusual noises | Schedule a brake inspection promptly to identify the cause before the problem gets worse. |
| Stop Driving Immediately | Severe shaking, grinding, burning smell, brake warning light, suddenly soft or unusual brake pedal, significant pulling or reduced braking power | Stop somewhere safe and arrange professional assistance. Do not continue driving. |
If you notice a change in the braking performance, have it inspected.
How Mechanics Diagnose Brake Vibrations
When it comes to diagnosing brake vibrations, a good mechanic will start by finding the source of the vibration, rather than immediately replacing the parts most commonly blamed for it.
Usually, the diagnosis starts with a road test to reproduce the vibration and determine whether it is felt in the steering wheel, brake pedal or throughout the entire vehicle. The road test will also help mechanics understand if it occurs at speed or not. Following the road test, a technician may measure rotor runout and rotor thickness to identify excessive runout or disc thickness variation.
Brake pads will be checked to ensure there is enough material and to look for signs of uneven wear, glazing or other potential problems. The calipers and other related hardware will be inspected as well. Other areas a mechanic might inspect include the ball joints, tie rods, wheel bearings and bushings, wheels and tires.
How Much Does It Cost to Fix Brake Vibrations?
Because so many different things can cause brake vibrations, and because it's a symptom of a problem, there isn't a standard repair price. For Arizona drivers, the costs can range from a relatively inexpensive wheel balance to substantially more expensive brake or suspension repairs. Adding to the equation is the vehicle make and model, the quality of the parts you choose to use and any labor requirements.
| Possible Cause | Typical Repair Needed |
|---|---|
| Wheel/tire imbalance | Wheel balancing |
| Worn brake pads | Brake pad replacement |
| Rotor runout/thickness issues | Rotor resurfacing or replacement |
| Sticking caliper | Caliper service or replacement |
| Worn wheel bearing | Wheel bearing/hub replacement |
| Suspension wear | Repair depends on affected component |
An inspection is always necessary to get an accurate estimated brake-vibration repair cost.
How to Prevent Brake Vibrations
Performing regular maintenance can help reduce the chances of developing a brake vibration. Regular maintenance includes routine inspections, replacing pads at the right time with quality parts, and servicing the rotors and other hardware as needed.
Brake fluid should also be routinely checked and serviced according to the automaker's specifications. Tire rotations, wheel balancing and suspension inspections can also help catch issues that might lead to brake vibrations.
Your driving habits in Arizona can also make a difference. When driving down to Phoenix from Flagstaff, use a lower gear if appropriate to help control speed and reduce constant brake use.
Frequently Asked Questions About Brake Vibrations
Why does my steering wheel shake when I brake?
The short answer: a shaking steering wheel often points to a problem affecting the front brakes, or other components in the front of the vehicle like the wheels, wheel bearings or suspension components.
Can warped rotors be repaired?
In some cases you can repair warped rotors by having them "turned" or resurfaced. This is an option if they will remain within the automaker's specifications and still have enough material remaining.
Is it dangerous if my brake pedal vibrates?
It can be dangerous if your brake pedal vibrates. Some pulsation can come from variations in rotor thickness, but if you experience severe vibrations along with other things like pulling or grinding, you will want to stop and have them inspected right away.
Why does my car only shake when braking at high speeds?
When you are driving at high speeds, everything is moving faster and, as a result, small variations in the brake rotors or the wheel balance can be more noticeable. A professional inspection can isolate which system is causing the vibration.
Can bad tires cause vibration when braking?
Yes. Tire damage, uneven wear, imbalance or wheel problems can create vibration that becomes more noticeable when braking shifts weight toward the front of the vehicle.
Should I replace brake pads and rotors together?
Not necessarily. Rotor condition, thickness and manufacturer specifications should determine whether replacement is required. However, damaged or excessively worn rotors may need to be replaced along with the pads.
How long can I drive with brake vibration?
There's no safe universal mileage. Mild vibration should be inspected soon, while severe shaking, grinding, pulling, burning smells or reduced braking performance means you should stop driving and have the vehicle evaluated.
Feeling Your Car Shake When Braking?
Brake vibrations rarely fix themselves and can become more expensive if the underlying problem causes additional wear. The ASE-Certified Technicians at Gemba Automotive can inspect your braking system, identify the root cause and recommend only the repairs your vehicle actually needs. Schedule your brake inspection today and drive with confidence.