Example of how to measure the thickness of the rotor and check if you need to replace it

August 15, 2023

When it comes to measuring the thickness of your brake rotors and determining whether it's time for a replacement, the process is relatively simple and can be done without removing the rotor itself. Most modern cars allow you to access the rotors without taking off the tire, although in some cases, depending on the type of rims you have, tire removal may be necessary to gain full access.

To begin the measurement, once you have direct access to the rotors, you can use a caliper measurement tool. This tool is readily available and can be easily purchased from an auto parts store or online. With the caliper, you can accurately measure the thickness of the brake rotor.

Here's a step-by-step guide on how to measure the rotor's thickness:

1. Ensure Safety: Before you begin, make sure your vehicle is parked on a level surface and the parking brake is engaged for safety.
2. Locate the Rotor: Identify the brake rotor; it is a flat, disc-shaped component that sits behind the wheel.
3. Caliper Preparation: Set your caliper measurement tool to measure in millimeters, as this is the standard unit for rotor thickness measurement.
4. Measure the Thickness: Gently place the caliper on the rotor's surface, making sure it is flat against the metal. Take note of the measurement displayed on the caliper screen.
5. Compare with Specifications: Once you have the measurement, you can cross-reference it with the nominal thickness specified for your vehicle's make and model. This information can usually be found in your vehicle's manual or online.

For instance, let's consider a practical example: testing the 2018 Dodge Charger RT's rear rotors. The specifications for this vehicle state that the rotor thickness should be 21.8mm. In your case, after measuring the rotor's thickness, you find it to be 20.00mm. Since the measured thickness is below the recommended nominal thickness, it indicates that it's time to replace the rotor.

Considering the vehicle's mileage of just over 70,000 kilometers, it's not unusual for the rotors to wear out and require replacement.

How to measure in pictures:

Link to the parts list: https://www.allrotors.com/vehicle/2018/dodge/charger/BR,BD-REAR-CMD,PD-REAR/ we know it is venter rotors since the trim is RT, so you click on the part, and get to the following page: https://www.allrotors.com/part-1009-BR53024

Here is the exmaple of speciications table:

Once you've identified that it's time for a new rotor, you can explore our parts search to find the specific replacement part that matches the measurements you just took. Ensuring your brake rotors are in proper condition is crucial for your safety and the efficient functioning of your vehicle's braking system.

Remember, regular maintenance and timely replacement of worn-out brake components will contribute to a safer and smoother driving experience.