Car owners often know just enough about their cars to keep them moving from day to day. But that says nothing about getting them to stop! While all aspects of car maintenance are filled with myths that are believed even by those who really should know better, brake repair seems particularly susceptible to old wives’ tales and outdated information. Even if your sole contribution to the subject involves taking your car to the mechanic when you hear a squeal, it pays to know when someone is telling you something that isn’t true. Here are a few myths that should be put down.
Rotor Thickness Is Based on Heat
This is one of those “facts” that is believed even by those who have some level of expertise in brake repair. The problem isn’t that it doesn’t sound plausible-most myths do, on some level-but that it just isn’t true. The thickness specifications for a car’s rotors are not based on heat, but rather how much distance the caliper pistons would have to travel if the pads were worn all the way down. The problem lies in the fact that if the pads are worn all the way down and the rotors are no longer thick enough, the piston could begin leaking. If that happens, it could become dislodged and you have complete system failure. Heat has nothing to do with it.
The Big Difference Between Pads
Auto manufacturers and brake repair shops that want to sell you a higher priced item will often talk about the differences in hard and soft pads. Many of these differences are not important from a performance standpoint. Rather, they are terms used in engineering and manufacturing to describe compressibility. And they are used not to describe issues of performance, but rather to ensure a quality control standard. While it can affect driving by making the pedal feel a little more or less responsive, it does not affect important issues such as rotor wear or pulsating in the brakes.
Hoses and Drag
It is a commonly held belief in the brake repair industry that a worn hose can cause your braking system to start dragging. This is rarely the case. The theory is that damage to the hoses causes a flap that will prevent the proper amount of pressure from getting out at the point of the caliper. This is seldom the cause of dragging braking systems. Rather, the problem is down to a caliper restriction due to the emergency braking system being stuck or some issue with the metering valve.