Is your car pulsating? Are the brakes warped? Have they gouged? Are they excessively thick? The answer to these questions lies within your rotor. The good news is that there are a number of solutions that can solve this problem. Below are some simple methods you can use to isolate and fix the problem. These tips can be used to fix a variety of brake problems, including pulsating rotors.
Warped brake rotors
Worn brake rotors aren’t the only sign of a problem. Your vehicle might also be wobbling and pulsing when you apply the brakes. Minor warps won’t cause such symptoms, but severe warps will. If you notice any of these symptoms, it’s time to take your car to a mechanic. Warped brake rotors can cause your brakes to stop working properly or even completely.
Whether you drive slowly or quickly, the signs of warped rotors can be difficult to spot. Your steering wheel may vibrate when braking or you may simply feel a pulsating sensation under the driver’s seat, nevertheless it is a good idea to monitor and investigate the cause. If you have a habit of braking heavily at high speeds, you can increase the risk of warping rotors due to the rotors constantly operating at higher temperatures.
Gouged rotors
A typical example of gouged brake rotors is one on the front rotor. The gouge isn’t very deep, and it looks like glue, oil, or grease stuck to the outside edge of the casting. On the other hand, the gouge in the rear rotor is a circular groove cut into the surface, likely due to worn brake pads. Regardless of the cause, it is dangerous and should be repaired immediately.
There are several different methods to repair gouged brake rotors. First, you can resurface lightly gouged rotors by using a brake lathe. In addition, you don’t have to remove the thickness. But if you’re dealing with a deeply gouged rotor, you should consider getting new ones. In most cases, machining a brake rotor will cost you as much as buying a new one.
Excessive disc thickness variation
Excessive disc thickness variation can cause your brake rotors to pulsate. This is caused by uneven transfer of brake pads to the rotor. The uneven transfer creates heavier deposits, which show up as dark spots or stains on your rotor. These deposits differ in their coefficient of friction when hot. These deposits are only microns thick, but they can be easily removed with a brake lathe and correct by selecting new brake pads that are designed for higher temperatures.
To isolate and repair this problem, a vibration-based approach is used. This algorithm is able to detect the fault against various other vibration sources, including the master cylinder pressure and wheel speed signals. It can then isolate the brake rotor fault for all four corners using wheel speed signals, and the rear rotor fault exhibits less vibration caused by the master cylinder.
Caliper runout
If your brake rotors are pulsating, you can diagnose the problem by inspecting the rotors for runout, then clean them and replace them. If you find that they are not running within the tolerance set in your vehicle’s TIR, you will have to reindex the rotors. If the problem persists, a new caliper will be needed.
The pulsating sound is caused by excessive runout. Depending on your vehicle and brake system, there are different types of excessive runout but all cause a surging or pulsating feel when you brake. Excessive runout causes a high and low spot in the brake pads. When a wheel has excessive runout, this causes brake rotors to vibrate.
Most pulsation complaints can be attributed to incorrect installation and torque specifications of the wheel. When experiencing pulsating brakes, you can try and isolate to the front or rear of the brakes by driving in a straight light and using your handbrake to slow the vehicle down and take note if the pulsating occurs. If you cannot feel the vibration it can be isolated to the front brakes, if you do have a pulsating feeling, it can be safe to say it is attributed to the rear brakes. To fix the issue you have with pulsating brakes, you really have two options. That is to either machine the rotors provided they are thick enough and within legal limits so that the surface is smooth once again, noting that this due to the stressed metal, the rotor can return to its warped shape down the track. The other option is to replace the rotors with new ones, this can be a significant cost, however due to the importance of the brake rotors and brake system in slowing a vehicle safely on the road, it is never a good idea to compromise on safety for cost savings.