This question usually relates to the brake pads. The lifespan of any given set of brake pads is dependent on a very wide set of variables ranging from how you drive to ‘science-y things’ like physics. Mechanics and manufacturers have a loosely agreed upon mileage range from around 30,000 to 70,000 miles, but stories of pads lasting a mere 100 miles to an amazing 100,000 miles exist too.
So, why the wide range?
Brake pads come in many types and compositions – from composite to metallic to ceramic – and are attached to an even more confusing array of brake systems drums and rotors, all of which affect the life of the pad. Add to that the mix of heat, pressure and friction in amounts that would surprise you and it becomes easy to see that the brakes, especially the pads, are some of the hardest working components in your car.
Pads generally come in four types: organic, semimetallic, metallic, and synthetic. Each of these types has their own characteristics that must be weighed against brake pad life:
- Organic: Made from non-metallic fibers bonded into a composite material. Probably has the best stopping power, but wears the fastest.
- Semimetallic: This pad is a mix of organic material and metals These pads are harder and more resistant to heat.
- Metallic: Once used extensively in racing. Advances in organic and semimetallic pad composition have made metallic pads almost obsolete.
- Synthetic: Also often referred to as ceramic pads. These pads weigh about half the weight of the average semi-metallic pad, they are stronger, have better cold and hot stopping power and they last much longer than the average pad. They also cost about twice as much.
At its most basic, a brake system converts your car’s directional energy into heat energy through friction – namely the pads pressing against the rotors. How much energy getting converted is determined by the cars weight and how much the speed need to change (ie 70 mph to 45 mph or 60 mph to 0 mph).
How much heat? The pads on the smaller car going 60 miles per hour might reach about 450 degrees Fahrenheit during an emergency stop. And this, of course, can affect the life of your pads.
Given all this and more, the best way to handle pad life is to have us check them during your routine oil change. Regardless of how long they may last, always pay attention to the signs of brakes going bad – fading power, loss of power when the brakes get hot, or pulling to one side or another during braking.