| “My
Brakes Are Making Noises. Do I Need New Brakes?"
The piercing, high-pitched squeal of defective
brakes. When you hear it next to you from another
car, it’s annoying. When you hear it from
your own car, it’s scary.
When is a little squealing just a natural mechanical
sound of brakes doing their job, and when is it
a sign of serious mechanical failure?
Many mechanics will say that squealing from your
brakes – even brakes on a reasonably new
car or new brakes recently installed on a used
car – is “normal.” That’s
a misnomer. The condition is never "normal,”
but it is "common."
Modern brake pads (the plates used to protect
the main metal parts in your braking system) and
their linings are no longer made of asbestos (thanks
to the EPA), but of tiny slivers of metal and
other materials compressed tightly together. These
high-tech brake pads and linings are much harder
than asbestos. They have excellent friction qualities,
but, unfortunately, they often make noise because
of the metal fibers contained in them. If you
rub metal on metal, even if it’s nearly
microscopic metal fibers, you can imagine how
you’re going to hear some squealing.
The trick is to determine whether the noise is
a problem or just an annoyance.
Sometimes the sounds are the result of tiny variations
in the surface of the pad. The newer type pads
often don't conform as easily to the surface of
the rotor. For example when the perfectly sized
asbestos pad (with its snug fit to your brake
parts) was replaced by the high-tech metal fiber
pad, either the newer pad wasn’t made to
fit quite as well – or the metal fibers
don’t adhere to the brake part as efficiently.
In such cases, the imperfect fit will leave tiny
gaps in the brake pad’s service, leaving
room for slight friction that can give rise to
a squeal. In such cases, it’s not a major
problem and not worth worrying about as a driver.
A squeak or squeal may also be the result of
vibrations. If you've had a new set of brake pads
installed and are hearing this sound, have the
brake work re-checked by the mechanic that did
the work. Chances are something was not installed
properly. They should be looking for loose parts.
Changes in temperature or changes in the moisture
content of the atmosphere also affect friction
characteristics that can set off a round of squeaking
and squealing. In these cases, intervention by
your mechanic isn’t necessary.
However, when should you
consult a professional to look at your brakes?
- Drip, drip, drip. First, look down where car
was parked after you move out a parking space.
Are you leaking break fluid? You’re checking
for stains or small puddles of fluid that don’t
look like oil or coolant. Motor oil will probably
have a brown or black look and feel slimy to the
touch. Coolant will appear green and more watery.
Brake fluid can look like fresh motor oil, but
it doesn’t have that slimy feel. You’ll
need to get your hands dirty, but check those
puddles. If you’re leaking break fluid,
consult a mechanic. You may need to check the
seals or bleed the brake lines.
- Squeal, squeal, squeal: If the noise from your
brakes is constant, you probably have a problem.
Consult a mechanic immediately. He or she will
check the brake calipers, brake shoes, master
cylinder, etc. The cost of the potential repair
will vary according to the fault.
- Scrape, scrape, scrape: One sound you should never
hear from your brakes is the horrible scraping
of metal on metal. In such cases, you have no
brake pad left and are literally stopping your
car by grinding your metal brake parts against
each other. After only a few instances of this
metal on metal friction, your brakes parts will
be absolutely ruined. As soon as you hear such
metallic scraping, call a tow truck and get to
a mechanic. The money you spend on the tow will
be nothing compared to the money you’d spend
on an entire new brake system.
So, your brakes requires a little detective work
on your part. A sharp ear, a few dirty fingernails
and some common sense will keep you going –
or, in this case, stopping – for countless
miles to come.
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