The Breakdown on Your Brakes
By: Grant W. Repsher
Understanding the two brake systems
What to watch out for
What to expect from your serviceWhen you break it all down (no pun intended), a car can really only do three things: accelerate, turn, and stop. No wonder brakes require the amount of attention that they do.
Brakes are arguably the most critical component of your automobile, for obvious reasons: the ability to effectively and consistently "scrub off speed" may sound like a given, but your brake system is heavily used and therefore warrants particular attention, not only from a safety perspective, but also from that of performance. Even in automobile racing, a real enthusiast will tell you that it's not just about speed, but a car's ability to brake that ultimately wins races.
In order to understand the how and why of brake repair, you first have to get to know the two types of brakes: drum brakes and disc brakes. In essence, a drum braking system works by pressing brake shoes outward against the inside of a round metal drum. Disc brakes, on the other hand, use brake pads to squeeze a spinning metal disc in order to slow (and stop) your car.
Drum brakes are becoming less common and today generally only show up on the rear half of some domestic vehicles, including economy cars, mini-vans, and light trucks. They operate on the same principle as the more prominent disc brakes -- utilizing friction.
Disc brakes, meanwhile, are the preeminent choice for all manufacturers; even those employing drum brakes in the back will invariably have disc brakes in the front. In short, this type of brake system is superior in terms of design and essentially operates like a drum brake turned inside out. This type of brake system is most likely what you have on your current vehicle, so we'll focus our analysis on it.
For maintenance purposes, the issues you'll most likely have to deal with are pads, rotors, and fluid. Because the entire system is based on the principle of friction, the components involved are in immediate contact with one another and wear down over time and with continual use. While many of the components are designed to last the life of the vehicle -- such as the master cylinder, calipers, and ABS unit -- others -- like the pads, rotors, and fluid -- do need to be replaced. How often depends on the degree to which the car is used and abused. But the typical lifespan for these parts is generally about 50,000 to 75,000 miles for brake pads and fluid, and 75,000 to 100,000+ miles for rotors.
The state of your brake system is typically checked at regularly scheduled service intervals that involve more than the basic lube, oil, and filter service. But there are telltale signs you can watch for that indicate you might need a repair before your next service. They basically play to three of your sense: hearing, sight, and tight.
Hear No Evil
For example, a grinding noise coming from any of the wheels could be a sign of wearing pads or rotors. Squeaking or squealing brakes, however, don't necessarily mean your brakes aren't in optimal working order; some systems are simply noisier than others due to materials used and design (if, however, there's a major change in the noise you usually hear, that could be cause for concern).
See No Evil
Likewise, if you notice an unusual accumulation of dark dust on your hubcaps/rims, especially on the rear wheels, it may be a sign that your brakes and/or rotors need attention. Most vehicles have a front brake bias, meaning that the front brakes play a larger part than the back brakes, so it's common to see some dust on the front. If, however, you see brake dust accumulating on the rear wheels, or an unusual amount of it on the front wheels, you're wise to take your vehicle in for a check-up.
Feel No Evil
Then there's the feel of your vehicle as you drive it. Over time, if it feels as though you have to put more pressure on your brake pedal to produce stopping (also known as "fade"), or your brake pedal nearly touches the floor of your car when you attempt to stop, it may be a sign that there's an issue with the pads and rotors, or you may have a problem with your brake fluid.
A word about brake fluid: it must endure high pressure and extreme temperatures, and can therefore break down or leak over time. It should be replaced during every major brake service, but this could be required more often in older vehicles or those with higher mileage. When speaking with your service advisor, you'll hear the terms "brake flush," which refers to draining the system of its old fluid and replacing it with new stuff, and "bleed," which is the procedure to remove any air bubbles or unequal pressure from your brake system.
When it comes to price, you'll find it varies. A full set of pads and rotors can cost anywhere from $250 to $800, depending on the make and model of the car. A brake flush service (which may include a bleed) should typically run you $50 to $120.
If you're using a dealership for your service, it makes sense to call at least two ahead of time to compare prices. While they'll tell you your system will need to be checked to determine exactly what needs to be repaired, the quotes you receive will still be helpful in identifying the more cost effective location.
If you're using a non-dealer facility (such as an independent or chain repair shop), you'll want to be armed with some basic vernacular to illustrate your knowledge and avoid being taken advantage of. Because rotors last longer than pads, for example, you might want to suggest that the rotors simply be "spun" as opposed to replaced entirely (just know that some dealers and shops only provide full replacement service, so spinning your rotors may not be an option).
Additionally, if you ask, any shop should be able to tell you what "percentage" of life is left in each of your components. Not only is this beneficial in helping you determine whether or not you can postpone your brake service a while, but it also illustrates that you're unwilling to pay for unnecessary work.
DIYers
Replacing brake pads is generally a fairly straightforward task, so you can certainly save some money by completing this service yourself if you have the appropriate mechanical experience and supplies. If you need to go out and purchase a jack, jack stands, caliper tool, or model-specific service guide (Bentley or Chilton), you probably won't save enough to make it worthwhile. But if you happen to own all of these already and have worked on cars before, you might consider the do-it-yourself approach.
Grant W. Repsher is the founder of Servassist Online. He is a writer with Automotive News, the auto industry's premier trade publication, and a former contributing editor with the AIADA (American International Automobile Dealers Association). To contact Grant about this article or to suggest future topics, please click here.
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