rev up your engines,
today I'm going to talk about brake systems on your car, when certain things
happen they tell you it's time to have the brakes fixed
now the most common problem is, the brake pads just wear out, you hit the brakes you
start to hear a noise, now these brake pads are still pretty good, they're
getting thin but they haven't gotten to the metal backing part, when the pad
material wears so thin that it's worn through to the metal backing, you'll hear
horrible noises as the metal grinds against the rotor, now some brake pads
have little squealers, they're a little metal rod that comes out and when you
brake pads get thin, that little Squealer will hit the rotor and you'll
hear it squeaking as you're driving, so when you hear that noise, go to your
wheels and check them, see if the brake pads are really thin, it's easy enough to
do on many cars like this Lexus, the wheels have holes in them so you can
look inside with a flashlight and see how thick they are, and in this case
they're pretty thick so you really don't need to change them, but here's the
kicker, let's say you hear them squeaking, but then after a while the squeaking
noise goes away, well that little metal Squealer can break off, then you won't
hear any noise until the metal gets down to the metal and it's too late, so once
you hear that squeaking it's a good idea to test them to make sure that they're
not thin and it's just time to change the pads, that's the cheapest thing to do
anyways, now like anything else, things aren't always that simple, a lot of times
car brakes will just squeak, because discs are open to the air and the rotors
get surface rust because they're steel, and they'll often make little noises now
and then, and if you pull them off and you see that, hey there's plenty of brake
pad left and there's nothing dragging and no fluid leak, and a lot of guys will
just live with that, and realize that as they age, some brakes just make squeaky
noises, now as a tip to stop squeaking noises, my advice is buy high-quality
brake pads, I personally found that the Akebono
a ke Bo I know it's a Japanese company, pads are the best I've had customers
that even gouge their rotors with their old pads, but they didn't want to spend
much money on their old car because it was a junker, so all I did was put on Akebono
pads and they didn't make any noise at all after that, so they're very good pads
now the next common thing that goes wrong with brakes is, you step on the
brake pedal but it sinks to the floor, maybe
not all the time but some of the time, now there's three things that can do
that, two are pretty easy to check out, but the third the ABS system is not, so
we'll start with the simple one, when you step on the brake pedal there's a rod
that goes through the firewall, and then under the hood of the car
the rod pushes the brake master cylinder that sends pressurized fluid to all the
wheels, so the most common reason that you step on your brake pedal and it goes to the
floor is that there's a leak in the system somewhere, so first you go to each
wheel, you look at the caliper see if it's wet and it's leaking, it's got a
rubber hose, the rubber hose can leak and then you check each wheel that way to
see if there's fluid leaking, now brake fluid is clear and it's very slimy, so
if you want to make sure it's the right stuff, just get some put a little on your
fingers, you see it's real slippery has a unique odor, and you see that leak and
then you got to fix that leaking area, now external leaks are pretty easy to find
you're gonna see the area leak and it'll be all wet
but sometimes the brake master cylinders themselves go bad, but they can go bad like a
bad heart valve, it can leak inside itself, you won't see anything leaking in
that case you really have to take the brake master cylinder off, and if you see
that the backside, the seal is wet it, means it's leaking or sometimes they just leak
internally and they don't make any pressure, in that case you just get
another brake master cylinder and install it, if it's not the master then it
starts to get complicated, it could be the brake booster, back here is the brake
booster, it's what boost power to give you power
brakes, and when the booster goes bad you can get a pedal that goes to the floor
but here's a classic way of testing it, if the engine is turned off in the car
and you step on the brake and it's nice and hard, but then you start up the car
and then hit the brakes and they go to the floor wow, that's a great way of testing
if the booster is bad, when the car is running and the booster has all its boost
pressure, and then the pedal sinks, it means that the booster has gone bad, but
there is one scenario in modern cars if you brake sinks to the floor that can be
really complex and expensive to fix, and that's anti-lock braking systems
there are very complex braking systems, you can see the brake pressure that
comes to the master cylinder goes to this gigantic solenoid, that has valves
it's computer run, the wheels have ABS sensors that measure how fast
the wheels are turning, and the computer reads the speed that the car is going to
see if all wheels are stopping at the same speed or if one is stopping less than
the other ones, it will modulate how the brakes break so you don't pull the
one side or the other, and then when this system breaks down, you have to have a
very complicated computer like this launch X431 and I have that
professional mechanics use, we have to analyze the ABS system, check all the
actuators, check the speed sensors, and a lot of times if you're lucky it will
have an ABS code and we'll at least get a generic area where the problem is, so we
can pinpoint what's wrong and fix it, needless to say that's not something you
can do at home yourself, but fortunately in most modern cars, ABS systems are
failsafe systems, so if your ABS system breaks down and your ABS light comes on
on most cars it will return to normal non ABS braking, and you'll be able to
stop your car fine, it just won't have anti-lock braking capability, so if one
wheels and water and ones on dry pavement, it's gonna slide around, and I
do have to say, a lot of my customers when I analyze an ABS problem they find
out they need a new modulator and the modulator is like fifteen hundred dollars a
lot of them will say, well I'll just live without ABS and just have normal brakes
and even if say, somebody told you you needed a modulator, you can't really
replace it yourself, because to bleed the air out of them, you need one of these
computers that has various steps that opens and closes the solenoids to get
the air out of the system and if you're putting a new one in, the new one's gonna
be full of air and it can be a real job even with one of these sometimes it takes
three or four hours to get all the air out of the system, and my last tip is
this, speaking of air in the system, a lot of guys will say, oh I need to bleed my
brakes I have air in the system, well bleeding your brakes if no work was
done on the car, isn't gonna really fix anything because, if there's air in the
system there's a reason there's air in the system, maybe the master cylinder
sucking air, maybe you got a leak in a hose and when you take your foot off the
brake it sucks air in, but if you do have air in your system, you want to find out
why and fix it don't think that bleeding it out is gonna fix anything by itself
so now you know a little bit more about brakes,
and when you need to have them looked at, and what to do about it so you can drive
down the road safely without smashing into people, so if you never want to miss
another one of my new car repair videos, remember to ring that Bell!