Hearing strange noises or feeling vibrations when you hit the brakes?
It could be your rotors acting up.
The big question is — should you resurface or replace them entirely?
We’ll give you the full lowdown on rotor resurfacing, how it helps your car, and the key signs that it’s time to book the service. We’ll also discuss whether it’s better to replace or resurface rotors so you can make an informed decision.
This Article Contains
- What’s Brake Rotor Resurfacing?
- How Much Does It Cost to Resurface Rotors?
- 6 Telltale Signs You Need Rotor Resurfacing
- 4 Major Benefits of Rotor Resurfacing
- Rotor Resurface vs. Replacement: Which One Do You Need?
- 5 FAQs on Brake Rotor
What’s Brake Rotor Resurfacing?
Rotor resurfacing is the process of removing a thin layer of the rotor’s surface using a brake lathe (a tool for fixing noise, vibration, and uneven wear after heavy use of brakes).
It essentially helps eliminate corrosion and brake pad deposits, smoothening out surface irregularities that may be causing braking vibrations.
But what leads to these surface irregularities?
The metal surfaces on rotors come into contact with the brake pads to slow down and stop your vehicle. Over time, the constant friction leads to a worn rotor surface, creating the need for resurfacing.
This brake service procedure is usually accompanied by a brake pad replacement to create a ‘new’ surface for maximum brake pad friction.
NOTE: Disc brakes use brake rotors (also called brake discs). Some vehicles may have disc brakes on the front wheels and drum brakes on the rear. In a drum brake system, brake shoes press outward against the inside of the brake drum to create friction and stop the vehicle.
Next, let’s explore the cost of rotor resurfacing.
How Much Does It Cost to Resurface Rotors?
The cost of resurfacing rotors varies based on your local labor rates and the vehicle type, but it typically ranges from $20 to $60 per rotor.
The level of wear on your brake discs plays a big role in the final cost. Additionally, if other brake parts, like the pads, also need servicing, the total price can increase.
So, how can you gauge if your car needs this brake service?
6 Telltale Signs You Need Rotor Resurfacing
Visit an auto repair shop ASAP if you notice:
- Vibration in the steering wheel when braking at high speeds, often due to a warped rotor
- A feeling of shaking through the seat or brake pedal, usually due to a rear rotor problem
- Grinding noises when braking, caused by corroded or worn-out pads
- Squealing sounds during braking, often from glazed or contaminated rotors
- Noticeable grooves around the edge of the rotor surface
- Brake pads wearing out rapidly
Once your mechanic resurfaces the old rotor, it can restore proper brake disc function and deliver other key benefits.
Keep reading to find out.
4 Major Benefits of Rotor Resurfacing
A polished rotor surface can help:
- Extend rotor life: Resurfacing preserves a large part of the rotor’s usable material by removing only a thin surface layer. This helps the rotor last longer and postpones the need for a costly brake rotor replacement.
- Improve braking performance: A resurfaced rotor ensures better contact with the brake pads, resulting in smoother stops and shorter stopping distances.
- Reduce noise and vibration: Resurfacing can eliminate unusual noises or pulsation during braking, making for a quieter and more comfortable drive.
- Extend brake pad lifespan: A smooth, resurfaced rotor prevents uneven wear, helping your new brake pads last significantly longer.
However, resurfacing can’t fix all rotor surface imperfections. Sometimes, the best solution is a new brake rotor.
Rotor Resurface vs. Replacement: Which One Do You Need?
Deciding whether to replace or resurface brake rotors depends on their condition and the vehicle manufacturer’s specifications.
Resurfacing rotors can be a better option if:
- It meets the minimum rotor thickness requirement after the machining process. As a rule, it should have at least 0.05 inches of rotor thickness above the discard limit.
- There’s no significant structural damage like hard spots, cracks, extreme warping, or deep grooves.
- You want to give new brake pads a rust-free, flat rotor surface for optimal performance.
You should go for brake rotor replacement when:
- The old rotor is too thin, cracked, or warped — making it more prone to overheating and warping. A warped rotor will also fail to dissipate heat or withstand the hydraulic pressure of the braking system.
- The rotors are designed to wear down with the pads, which is common in newer vehicles with thinner rotors.
- You’ve already had multiple resurfacings, so getting a brand-new rotor may be more cost-effective.
If you’re still unsure about the right choice, consult a trusted mechanic who can perform a brake inspection and guide you accordingly.
NOTE: Brake rotors typically wear evenly across both wheels on an axle, so rotor replacement should be done in pairs. Even if one rotor seems fine, replacing both ensures balanced braking and prevents the vehicle from pulling to one side during stops.
Next, let’s go over some common queries about the brake rotor.
5 FAQs on Brake Rotor
Here are answers to clarify your doubts related to brake rotors:
1. What Is a Brake Rotor, and How Does It Work?
Brake rotors, pads, and calipers are the main auto parts in a disc brake system. The brake rotor is a heavy metal disc connecting the vehicle wheel to the wheel hub. When the wheel rotates, the brake rotor spins with it.
How do disc brakes work?
The brake calipers are suspended over a section of the rotor. During braking, brake fluid transfers pressure from the brake pedal to the brake calipers. The brake caliper then clamps the brake pads onto the brake rotor, generating friction to slow down the wheel and bring the vehicle to a stop.
2. What Causes Rotor Vibrations?
Rotor vibrations while braking are typically caused by:
- Brake pad deposits on rotors, creating an uneven rotor surface
- Excessive lateral rotor runout, producing a wobble
- An unevenly thinned or warped rotor
- Corrosion buildup on the brake rotor
3. Why Do Brake Rotors Wear Down?
Each time you apply the brakes, the rotor’s thickness decreases slightly.
However, the rate at which the rotor wears down depends on factors like:
- Brake pad type: Semi-metallic brake pads wear down rotors more quickly than organic or ceramic brake pads because of their metal content.
- Rotor quality: Defective brake rotors may come with hard spots and impurities undermining their durability and performance.
- Driving style: Rotors wear down faster with hard, aggressive braking. The frequent braking required in stop-and-go traffic also thins them, necessitating a brake job.
- Vehicle weight: Heavier vehicles require more braking power, creating extra wear on the rotor. The same goes for a vehicle hauling heavy loads or pulling a trailer.
- Terrain and environment: Mountainous terrain or icy roads typically require harder braking. Snowy and rainy regions also expose the rotor to salt and moisture, accelerating rotor corrosion.
4. What’s Rotor Runout?
Rotor runout refers to how much the brake rotor deviates from side to side when viewed from its front edge. It’s also called lateral or axial runout and creates a wobble during tire rotation.
Excessive runout can cause the rotor to wear unevenly, producing vibrations during braking.
Some causes of excessive runout include:
- Distortion from improperly tightened lug nuts
- Dirt between the rotor and hub
- Hard spots in cast rotors
5. How Does Heat Affect Rotors?
Heat impacts both rotor wear and braking performance.
Braking friction generates a lot of heat, which the rotor must absorb and dissipate. The disc section of the rotor handles this heat, releasing it through cooling fins (or vents) between the faces of the disc.
If a rotor can’t dissipate heat efficiently, it may overheat and warp. This may also damage other brake parts. That’s why vented rotors are typically used in front disc brakes, where the braking load is higher. The rear rotor, which handles less braking power, is often non-vented.
Fix Your Rotors for Better Control on the Road
If you’re unsure whether your pedal vibrations are caused by a worn rotor or other defective auto parts, your best move is to have a mechanic examine them.
An even better option is to rope in the services of a mobile mechanic like AutoNation Mobile Service. This way, you won’t have to drive an unreliable vehicle to a repair shop.
The best part?
We offer easy online bookings and a 12-month | 12,000-mile warranty on all repairs.
Contact us, and our technicians will be at your driveway in no time to resurface brake rotors, perform a brake inspection, or handle other car issues you’re facing.