Breaking Down Brakes - Part 1

In this Part One episode, I’m at LATTC with professor Jordan Cantillano talking through some basic and not-so-basic information about brakes that's helpful for everyone to know. We talk about pads, rotors, what normal wear actually looks like, and how much your driving style affects how fast things wear out. 

We also get into the stuff you’ll actually notice day to day—squeaking wear indicators, that steering wheel shake when rotors are uneven, and how to do your own check on pads and rotors. We talk about the importance of keeping your brake fluid fresh and how moisture can quietly change how the brake pedal feels over time. And more to come next week!

Check out LATTC's huge list of areas of study! There's a class for everyone.

Some suggested items to buy. If you buy using these Amazon affiliate links, it helps support the podcast!

Brake Pad Lining Gauge

Brake & Tire Gauge kit

Brake Fluid Tester

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Transcript

SPEAKER_01 0:00

The content of this podcast is presented for informational purposes, and the perspective and opinions expressed are based on the experiences of the host and guests and do not replace doing your own further research or having your car inspected or serviced at a qualified job. Hi, and welcome back to Good Karma Podcast, where I try to demystify cars one conversation at a time and help in peace of mind instead of panic when it comes to what's going on under your hood. And today we have a great topic for that, which is brakes. And I'm here at school at LATTC with my friend and teacher Jordan Cantiano, who teaches here, uh he teaches brake suspension and steering and heating and air conditioning as another class. And you've been in this field for many years. You started off even as a kid, you were already learning about cars. So can you tell us a little bit about you and how you got into this field?

SPEAKER_00 0:56

Um, I would say that I pretty much started by uh um, you know, family. Because um my family, like all most of the men in my family are they pretty much work, you know, labor work. So like I have a few uncles that are uh mechanics, and I have uh my father was a contractor, so a little bit of everything. But um, as far as like the mechanical side, like my uncles were, you know, kind of like street mechanics. I tell the students all the time, like, you know, like I learned a lot of bad habits from them. But then when I got into the industry, I really understood and learned more about that and how to do it the right way, not the wrong way, like they showed me. But you know, like I tell the students all the time, like sometimes they, you know, they show me some stuff that is good, some that isn't. But yeah, I mean, since I was a kid, they pretty much gave me a wrench and told me to figure it out and give me a few pointers, and that's how I learned, honestly.

SPEAKER_01 1:49

Do you remember? Was there any point when you were like, I really love that I know how to do this and I'd like to pursue it?

SPEAKER_00 1:55

Yes. Uh, I think the one there was one instance where um it's funny, funny that it's the topic that you know I'm most familiar with and the topic that I really worked really in depth with was a brake job. I was doing a brake job and um I couldn't figure out what was the problem. And uh what it was was we had a bad master cylinder. So the bad master cylinder was giving me uh, you know, a lot of issues with the with the pedal. And when it gave me the issues with the pedal, I you know, I'm thinking bleeding the brakes, doing this, changing the pads, and I couldn't figure out. And then I said, you know what? No, I I I really gotta get into you know the logistics of it. Yeah. Right. And that's kind of what's kind of took me to take it to the next level, right? Instead of just working in the backyard with you know my brother or taking cars apart, putting them back together and stuff like that. Yeah, that's what kind of made me take the next to the next step.

SPEAKER_01 2:45

Yeah. Um but there's so much joy in just tearing something down and figuring it out, of course. Even without the more technical background.

SPEAKER_00 2:55

Yes.

SPEAKER_01 2:56

Um that's so cool. I didn't remember that. I don't know if you should if you told us that story.

SPEAKER_00 3:02

Yeah, I mean, not that particular one where I were the one where I pretty much was kind of stuck in the bind, but I learned a lot of things with them. Like, you know, they were the type that you know they would do a break job, uh, you know, no lubrication, which we know I talk about in class, no torque. They would just tighten the wheels as tight as they could, right? Step on the step on the crossbar. I mean, I'm sorry, on the cross wrench, and you know, that's good to go. So I mean, I learned more when when I was in industry, and then um, you know, I when I was in industry, I came back to school. So I came back to school and I learned even more, which was you know a good thing too. It helped me understand, you know, not just how to use my hands, but also how to use my head on certain things like diagnosing and figuring things out, which helped a lot.

SPEAKER_01 3:50

Yeah.

SPEAKER_00 3:50

Um, and you know, I kind of put two and two together, and then that's kind of what I what I share with my students. So then they could learn, you know, a little backyard and you know, a little professional side too, you know.

SPEAKER_01 4:02

Yeah. Um well, so today I wanted to talk to you about um just some like sort of an overview on brakes, um, just something, you know, things that'll help the average person in terms of knowing how to identify problems, what to watch out for, the good practices for their own cars, um, maybe a little bit how to how to keep an eye on making sure you're not getting taken advantage of at a at a place, or at least I try not to put things negatively, you know, just just be more informed so you're sure you're agreeing to the right rotor.

SPEAKER_00 4:34

Exactly.

SPEAKER_01 4:35

With brakes, maybe we could talk about how the so let's start with brake pads. And maybe can you just do a quick explanation for someone like me who never used to know anything? Um, what do brake pads even do? And how does it relate to the rotors?

SPEAKER_00 4:52

I mean, you could you could kind of put it if you want to put it like in layman's terms, you could honestly say it's almost like a pair of shoes, right? You wear your shoes and then the bottom of your shoes they'll wear out within time while you're riding, while you're walking on the street, running on the street, whatever you're doing, they start wearing out and they lose grip, right? Almost the same concept, it's gonna wear out. So with brake pads, what happens is you have uh pretty much a friction compound that pretty much is what is going to make contact with the rotor. Okay, so every time we stop, that friction material is gonna touch on the rotor and it's gonna cause the car to stop. Okay, so what happens is within time, you know, depending also, and also I like I like to you know reiterate that it's not just that the brake pads are gonna wear out at the same time for everybody, it all it all depends on the driver. Yeah, right. Someone is very heavy-footed on stopping the car, pads are gonna wear out quicker. If it's someone that's you know doesn't drive at a rapid pace and slows down slowly, and things like that, you know, the pads are gonna wear, they're gonna wear longer and last longer for the for the for the consumer of the car, which is good to know.

SPEAKER_01 5:59

So that um that would translate to it's not necessarily by mileage or time to replace the brake pads, it's really how you drive and leads us nicely to the um the brake indicator. Uh so when you hear squeaking and your brake, yeah, you'll hear so so there's a difference.

SPEAKER_00 6:18

With the screech, and you'll hear a different like you'll hear a squeak, you can hear a scratching sound. Now, the one that you're talking about, the brake indicator, it's uh that is uh about two, it's about two millimeters in depth of the brake pad, which in most brake pads, when you reach two millimeters, it's usually that's it, they gotta go.

SPEAKER_01 6:39

Oh, and what do they usually start at?

SPEAKER_00 6:41

Uh maybe it's standard, roughly about 12 to 10 millimeters. Okay, they're usually for a brand new brake pad.

SPEAKER_01 6:47

So two, you've gotten plenty of life out of it.

SPEAKER_00 6:50

And like I told my students, like when we're measuring them, we we use what's called a uh uh brake lining gauge, and that gauge is it's a little simple tool that has like three color coordinations, like a green, yellow, red, and you could get it at your parts store, and it's like even on Amazon, you get it for like five, seven bucks, and that kind of will be a good indicator to say, Hey, you know, I have this much. Um, and it's also color-coded. So if you don't understand the millimeters or what's the right one, it'll kind of guide you and tell you what's good, what's cautious, and what's you need a replacement really soon.

SPEAKER_01 7:30

Yeah, and so also at the same time, if um you're being recommended new brake pads, uh, they should be able to give you a specific measurement, right?

SPEAKER_00 7:38

Yes, that is correct. That's part of the inspection that is being done on the vehicle that will tell you what is the millimeter spec on it. And in some of the leaderships they will actually will give you like a color coding on it, and then it'll say, you know, it's in yellow, and then it'll say it needs attention. And you know, you could take a better judgment on, you know, okay, maybe I'll do it on the next one. You know, if once they tell you it's red, it's gotta go. So sometimes those are things that you really have to check.

SPEAKER_01 8:00

Yeah, and um, once it's red, for sure, do it. You don't there's nothing wrong with doing it once it's in the yellow if you want to, if you feel like you can afford to do that.

SPEAKER_00 8:08

Yes, that's that's kind of like you know, like keeping on it, kind of thing, you know, like cautious. That's why it's yellow, right? Yeah, and usually the yellow will be like five, four millimeters. So it's like we're kind of at at the halfway point, a little bit going like 40% of the brake life, that's usually where you're gonna be at the yellow. So you're still halfway there, so you're still okay.

SPEAKER_01 8:27

Yeah, yeah. Um, and so once you do hear, if you do wear the brakes down enough that you start to hear the squeaking, that's just um an alert, really. Yes. Uh, because uh most cars don't have a I just found out some cars do, and correct me if I'm wrong, but most almost all cars they don't have a light that comes on when your brake pads are low.

SPEAKER_00 8:53

No, because because there's so so to to clear that one up. So there is so the one you're talking about is called the brake wear indicator. Okay, the brake wear indicator, it's an electronic, uh, electronic unit that's attached to the to the brake uh pad. It's just like a little probe that goes inside the brake pad. And what that does is once the brake pad reaches that particular point, the light will come on on your dash saying your brake pads are worn out.

SPEAKER_01 9:23

Oh, I misspoke then. I was just trying to say one the the what's the what's it called when you hear a squeaking the scratching sounds a little like a little scratching sound that's the brake, that's the brake pad indicator, but that's a metal piece, yeah.

SPEAKER_00 9:33

Like a little aluminum piece that it's so the it needs a very high pitched sound so you could hear it. Yeah, and sometimes when you're driving on the freeway, if you ever hear someone that you're driving next to you here, like a little scratching sound, it's usually there, it's usually that indicator that's saying, Hey, you know, change me. And that's why they make it from that material. So when it makes contact with it, it doesn't really scratch the rotor because it's a softer metal, but it does give you a very high-pitched sound, so then the driver could hear it.

SPEAKER_01 10:02

So when you if you hear that sound, it's not gonna be like it's not meaning, oh my god, your brakes are gone, your brake pads are gone or anything. So your car might not feel any different to you. So can you tell people the risks of just continuing to drive when once you hear that?

SPEAKER_00 10:19

Once you hear that, that's that's a sign like saying, take me in. Yeah, right. That's that's pretty much what it's gonna be. That's if you hear that sound, that's not something, oh, you know, six months later, no, because then if you wait six months later, then you might be metal on metal, and then you're damaging more components along the way. So that indicator means when you hear that sound, you know, it needs to be addressed like immediately. Right.

SPEAKER_01 10:43

Yeah. And one of the first things that will get damaged if you wait too long is the rotors, right?

SPEAKER_00 10:48

Rotors, the the piston on the caliper, um, you know, everything else that's attached to it can get damaged, right? Other things could get compromised too.

SPEAKER_01 10:57

Seals can burst, possibly, right?

SPEAKER_00 11:00

Because the piston only goes so far out. And if let's say that uh the brake pads are worn down too much, the piston could it could slide out of the caliper, um, because it only has a particular depth. So then if it comes out, now you're gonna have brake fluid all over the place and it's a mess. So that's why it's very important to make sure that you hear that sound, go go address it.

SPEAKER_01 11:22

I mean, and God forbid that happens when you're driving, now you're losing brake fluid.

SPEAKER_00 11:26

Pretty much, and not just that, but you pretty much won't have any any brakes.

SPEAKER_01 11:29

Yeah. Um, and as far as rotors, um, rotors also do need to be replaced periodically, but not necessarily every time you change your brake pads, right?

SPEAKER_00 11:44

Not necessarily.

SPEAKER_01 11:45

Um, maybe on newer cars, they they come thinner now than they used to.

SPEAKER_00 11:49

Yes, and then the thing of the thing about it is that it's it's all based on, you know, once again, like I said, how you drive. Like if you're a very heavy-footed driver, you know, the the brake pads are gonna wear more into the rotor. And when it does that, it it could uh pretty much mold the the rotors to a shape that you don't want it to shape, and that's what we like to call a warped rotor. So when it's a warped rotor, it's pretty much a rotor is going to be uneven. When it's uneven, then the when the brake pads try to make contact, that uneven surface is gonna cause a vibration. So a very common fix uh out in industry is a customer complaint would be I'm driving on the highway, and when I drive on the highway, my steering wheel shakes every time I step on the brakes. So, usually when that happens is because the rotor is warped, and that what's happening is that you have a flat surface that's not making contact with another flat surface. So just picture it where you have a flat surface that's trying to make contact with an uneven surface, it's going to want to make contact. And if it doesn't, then it's going to cause a vibration. And that's that's a very common thing that you see along the way.

SPEAKER_01 12:57

Um, and so now you just reminded me that um a person can look at their own rotors and look for some issues. Warpage is not one of them because that you have to use a tool to measure, right?

SPEAKER_00 13:09

Yeah, I mean, we do have a couple of ways of doing it. Um, like with the students, I have them check it. Um, of course, you never want to check it with a car just pulled in because the rotor is going to be hot. So you gotta let the cool the car cool down before you do any of this. So that's like the first disclaimer, right? You got to make sure that it's cooled down. And you could rub the back of your nail on the rotor itself, and you rub it from top to bottom or bottom to top, doesn't really matter. And what we're looking for is we're looking for waves. We're trying to see if we feel any like little waves. Like, like I tell the students, you should feel if I rub my nail from the bottom to the top, you should feel like the surface is smooth all the way across. We have that, then you know we're we we're we're in good shape. Now, if you feel like it's wavy or you feel like lumps or grooves or anything aside from smooth, then that means that it needs to be addressed. Now, there's two options. One, you could resurface the rotor, or two, you could replace it. So it's usually up to the customer at that point, whatever they decide to do. Um, resurfacing is a great alternative because it's cheaper for the consumer. And the brake rotors are usually meant to, you know, have extra life, yeah, aside from the first use, right?

SPEAKER_01 14:22

Right, aside from the first use. And so do you think it's good? I I feel like it's good for people to know the specs on their rotors, you know, like know the measurement you're you need to hear before you say, okay, yeah, let's just replace it.

SPEAKER_00 14:35

Yes, and then that's usually usually they'll do that, where like if the the alternative is, you know, I want to resurface my rotor, they're supposed to check. So they're supposed to measure uh the the thickness of the rotor. So when they measure the thickness of the rotor, they got to measure multiple points on the rotor to make sure that we have an even surface all the way around. And every rotor is gonna have a specific specification. That specification is gonna be what's called the minimum thickness allowed, yeah, which uh in most cases they'll you know they'll they'll say pretty much the rotor's junk once it passes, once it passes that number. So when the technician measures it, they're measuring for the thickness of the rotor. If it's above that uh specification, then you know they will give the recommendation. Oh, we could resurface the rotor. If the number's too close, then the recommendation is going to be to replace it. Yeah, yeah. But people gotta know that that's usually an option. Now, there's certain manufacturers that are not gonna want to resurface, like a lot of German vehicles, they don't want to do that. Um, certain manufacturers just their recommendation is replace. Yeah, um, they have the reasons. Um, but you know, that's usually what what we have. But just know that there's always that option to resurface a rotor, save a little money along the way.

SPEAKER_01 15:48

Yeah, definitely. And can you uh mention a little bit about um if a person looks uh just visually looking at the rotors, it um if they see very sometimes there's noticeably deep roofs or hot spots.

SPEAKER_00 16:00

Yes. So you could see hot spots, uh low spots, things like that. The hot spots they'll usually look like uh a different color. Sometimes it'll be like a bluish color. So that usually comes from excessive heat, the hot spots. So, like I mentioned earlier about you know, the drivers, you the heavy, the heavy-footed drivers are the ones that usually end up coming on coming across with these issues, right? Where you know they're applying too much, too much brakes, it's causing too much heat, and it's gonna put some put some damage onto the rotors themselves. So you could visually see those, yeah, and you could visually see the scratches, right? And you know, that whole theory that I said about the nail, right? If you rub your hand, your nail on the the rotor itself, right? You could actually feel those scratches and grooves of how deep they are, and you're not supposed to feel that now. Remember, I'm I'm saying I keep saying nail, right? You got to use the back of your nail, right?

SPEAKER_01 16:54

Right.

SPEAKER_00 16:54

Because what a lot of people get, and I see this happen in in the college a lot, where students they grab the rotor with their hands. That's one thing that we're not supposed to do. Because when we grab the rotor with our hands, our hands naturally produce oils, yeah. And the last thing we need is to put any type of uh oil onto the rotor, because what that that'll do is that'll cause uh for heat hot spots as well. So those particular spots that we do touch, it could create more heat in that particular spot versus the others because the oil is present, right? So you're creating heat. If you put heat on something that has oil, it's gonna get hotter there. I mean, it's just that's the way it is generally, right? And that same thing applies to the brakes. So try not to touch them with your bare hands.

SPEAKER_01 17:39

And so something I noticed um a few months ago, I don't know how I never saw this before. I mean, granted, it does not rain a lot in LA, but it was after rain, and I looked at my rotors and they were um almost orange.

SPEAKER_00 17:53

So they're rusted, yeah.

SPEAKER_01 17:55

And and so that, and then I I kind of freaked out. And then I started looking at other cars on the street and like, oh, they all have it.

SPEAKER_00 18:01

Yeah.

SPEAKER_01 18:02

And so there's some rust that's natural and oh yeah, it's part of it.

SPEAKER_00 18:07

It's it's good to go into. So it's I like like I tell a lot of my students, rust is like a big, it's it's a big no-no in in when it comes to brakes and undercarriage, everything underneath, because rust is a huge, huge problem along the way, especially if it's not addressed. Now, what you what you saw was it's just you know, the car sits for let's say overnight or two nights or three nights, right? Yeah, the longer, the longer it stays put without it being used, the rust is just gonna sit there. And like I tell the students, rust is like a plague. It's gonna sits there and it's gonna keep on growing and growing until it's addressed. But that's not nothing to worry about. As soon as you drive away, you maybe go a few blocks down, step on the brakes, and you look, you're like, it's gone. Yeah, it's just pretty much like a like a layer that just sits on top. That's it's normal for moisture and and rain in particular that will cause that, yeah. Right. But that's also another thing you gotta keep in mind. Like, let's say the car has been sitting for a year or two, and you have that rust that's just there. Now remember what I said the rust is gonna grow, the rust could grow deep into the rotor itself, and then now you'll have a deep rust pocket inside. So let's say that you do drive off for even though the car's sitting for a year or two, it's not you're not just gonna be able to crank it up and start it just like that, right? So, but let's just say that you did, right? The rust might not come off on that, and then what happens is the rust will just deep dig inside the rotor, and what you would probably have to do is replace it at that point, yeah, because the rust is gonna be too far deep, and there's really no way of I mean, you could keep resurfacing and resurfacing, but you don't know how deep it is, kind of a lot of waste of time, right?

SPEAKER_01 19:45

Okay, um so let's talk a little bit about um brake fluid because um I I know that there's a lot of people who don't even know you're supposed to change rake fluid. Um so great there's a few things that are important that I wanted us to bring up. Um one is that rake fluid is hydroscopic, yes, uh, which means it absorbs moisture. And so why is that important?

SPEAKER_00 20:20

Well, to know it's very important because a lot of people uh don't understand that you know it being a hydroscopic fluid, it absorbs moisture, and then moisture is a big, big faux of brake fluid. It pretty much, if you do get moisture inside the system, it it what it pretty much does, it's it kind of affects the the quality of the brake fluid, which means that it's not going to work the way it needs to. Okay. So now that being the case, another thing that it affects is you got to know one thing. Brake fluid has what's called a boiling point. So when it reaches a particular boiling point, that's pretty much like we mentioned the heavy footer again, the heavy footer, right? They keep on stepping on the brakes. If anybody out there has ever driven a vehicle and maybe pushed the pedal to the metal a little too much and stepped on the brakes, you're gonna smell some brakes, and you know, that usually happens because you know it's being overworked. Now, that being the case, a lot of people think, oh, it's only the rotors and the brake pads, but then again, the brake fluid also gets hot and it reaches a particular boiling point. So that boiling point, when it reaches that particular number, it could stop working. So what'll happen is when we talk about moisture, moisture, we know that uh water boils at what 212. Okay. So if we have water that boils at 212, and we have brake fluid that boils at about 400 degrees, right? It's a big difference. So if we're stepping on the brakes constantly, friction is being created, heat is getting created. So that fluid is only going to be able to take so much. So now if you mix fluid with water. The boiling point's gonna drop, which would what will happen is the brake fluid will lose its quality. So the boiling point will drop. And I would say it will drop a lot to the point where now my brake fluid won't work at high temperatures like it normally should because of this moisture. Now, with moisture, it's not something that if I look at my brake fluid, I'm gonna look at it and say, Oh, moisture's there.

SPEAKER_01 22:25

Right, right.

SPEAKER_00 22:26

You can't visually see it, right? But they do sell like this little inexpensive tool. That's it's called a brake fluid tester.

SPEAKER_01 22:32

Very cheap.

SPEAKER_00 22:33

Very cheap. Yeah, you're looking at five, ten dollars on Amazon. Yeah, just with two little triple A batteries, and you insert it into the brake fluid, and voila, there's your answer. It gives you pretty much also green, yellow, yeah. Green, yellow, red. Yeah, and it tells you how much it is. So you're looking at one percent, two percent, three percent, four percent of moisture. Now, once you reach the three to four percentile, that means that it needs to be replaced, and you'll see it on that on that meter when you submerge it and you get three three percent, it'll be in red, which means hey, you gotta you gotta change because the misconception here is why a lot of people don't do it, is because the brake pads they'll feel the same, right? But right, but like I tell my students, I've had cars come in here four percent or higher, and they change it, and all of a sudden, when they replace the brake fluid, they're like, Oh wow, the pedal feels firmer. But because you get so used to you get so used to it because you you're driving and you feel the same thing on a constant basis, and you're not gonna know the difference because it's very minuscule. Yeah, but then once you do it, you're like, Oh wow.

SPEAKER_01 23:37

I would notice that like on my my older car. Um, and then if I would rent a car, I'm like, oh wait, this brake pad is way better. I mean, this brake pedal feels much nicer than mine. Yeah, mine goes, I have to press all the way to the floor.

SPEAKER_00 23:50

And then that's the thing. It's and then it's a simple test. You open up the brake, the the brake fluid reservoir cap, you open it and you submerge it, and there's your answer. Simple. And that pretty much will tell you when I'm gonna replace it and when I'm not, right?

SPEAKER_01 24:08

Yeah. Also, you mentioned um, of course, you can't tell the moisture level by looking, but the the brake fluid will get dirtier and dirtier over time. So you can see if you look and you've never looked at it before, and all of a sudden you see it and it's pitch black, which I've seen, um then that's see that that could be two signs.

SPEAKER_00 24:27

It could be one that the brake fluid just never been changed before. I've seen it too many times where when was the last time you're changing? I don't know, right? So that's usually the the usual answer. But then there could be one that, like I told my students, I've had cars in cases where you know, a car comes in, we do a breakfast flush, and a year later it's pitch black. So then when that's where we have to come in and do an inspection, and and in most cases, what it is, it's um there's a dust boot cover, there's a dust boot uh seal on the brake caliper. And if there's any tears there, right, the dust from the brake, the brake dust or anything that's picked up on the road can go there. And it pretty much just transfers all the way up to the fluid, and that's what causes you know dirty fluid. But in most cases, you seals the system stays sealed, and usually when you see the black fluid, it's hasn't been changed in a long time. So when you look inside, you should see like a light amber color, um, almost like a very light golden yellow. That's usually what it's supposed to look like, right? So it's very, very clear.

SPEAKER_01 25:33

Okay, thanks for listening to my conversation so far with Jordan Cantiano. Uh, we had a really pretty in depth conversation, and I'm gonna save the whole second half uh for next week. Thank you so much for listening. Keep up with your oil changes, and I'll see you down there.