How to Replace Rear Brakes 2003-07 Cadillac CTS

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Hi, I'm Mike from 1A Auto. I hope this how-to video helps you out, and next time you need parts for your vehicle, think of 1AAuto.com. Thanks.

The items you'll need include new brake pads and rotors from 1AAuto.com, 13mm and 18mm sockets, a ratchet, and T30 Torx bit, groove jaw pliers or brake caliper compressor tool, torque wrench, a wire brush, brake grease, brake cleaner, a bungee chord, and a jack and jack stands.

Hi, I'm Tony from 1A Auto. To show you just how easy the repairs we do here can be done at home, we've brought in my friend Matt, who doesn't work on cars, and we're going to have him change out the rear brakes on this 2005 Cadillac CTS.

You ready to get started Matt?

Sure, let's do this.

Let's go.

To start off, we're going to remove the wheel. You're going to need this 19mm deep socket and a breaker bar. You're going to want to set that onto the lug nuts, and, to loosen them, just crack it counterclockwise a little, and then we'll raise the car up. You don't want to turn them off much more than about a half a rotation or so, because we need the wheel to stay on the car until we've taken the weight off of it with the jack and jack stands. We’re going to use a lift to make this easier to show you guys at home, but you should be able to do this in the driveway with jack and jack stands.

Now, we're going to finish removing all the lug nuts and take the wheel and tire assembly off of the hub. You can take the socket off of the breaker bar, spin them off by hand or you could use a ratchet if it's easier for you. Go ahead and grab ahold of that because there is a little of weight to the wheel and tire assembly. You can either grab the spokes of the wheel or the sides of the tire, lift up and off the hub, and set it down carefully.

Now, you're going to need this T30 Torx bit, extension, and a ratchet to remove this screw that holds the rotor onto the hub, which keeps our rotor upright—makes it easier to reinstall all of our brake hardware—but for now it's just in the way. Now, we're going to use a longer ratchet to get a little more leverage. We've got a flex head on here to make it easier and a 13mm socket. While you can do this with a straight ratchet, it's going to make it easier for you to remove these two 13mm bolts that hold the caliber onto the carrier. There you go. Once you've loosened them up with the ratchet, sometimes it's easier to just remove the hardware by hand.

To see if you can remove that caliper by hand, you're just going to want to grab it and pull towards the front of the vehicle. If it's stuck, we'll show you some tricks to get it off.

Just pull toward the front. Now you'll want this bungee cord, hook it through the holes in the caliper, and secure it up out of the way like onto this control arm or over to this spring here. All right, just be careful not to put too much tension on this rubber hose, as they can tear and cause a leak in brake fluid. We don't want to do that. Now, it's up out of our way until we need it.

Now, we're going to use that same ratchet with an 18mm socket to remove these two bolts on the back. What that does is it holds this carrier that holds your caliper, and your brake pads onto the spindle. Go ahead and loosen those up, and take them out. All right, those can be in there pretty tight, so if you want a longer breaker bar, we can get you one.

Am I going the right way? I should go up this way, right?

Just be careful when you're removing those bolts that you use one hand to support the caliper carrier when the last bolt comes out so you don't drop it. Remove the caliper carrier from the knuckle. There you go. Go ahead and grab both sides of the rotor, you might have to work it back and forth a little bit to break the rust loose or get it off the E-brake shoes, then pull it out and off the hub.

Now, we're going to clean and prep the brake caliper carrier to go back onto the car. We want to check these slides here for smoothness. Those are what allow the caliper to move in and out. As the piston compresses, that caliper is going to move to stay centered over the pads as they wear down. These ones aren't seized up, they're moving nice and freely. Let's go ahead and grab the boot here in the end of the slide, and pop it out of the carrier.

What would happen if these are seized?

If they're seized up, they're going to cause one brake pad to move where the piston on the caliber pushes in, and the other side won't be able to grab it to compensate; you'll see one pad is worn down more than the other. Go ahead and take a paper towel and wipe all that old grease off. Put a little bit of new break grease onto your finger, and apply a thin coat to the pin. You don't need a lot, you just enough to get a nice thin coat on there and keep it moving nice and smooth.

Go ahead and push it back into the boot. Go until it pops back onto that rubber collar there. Do the same thing to the other one. Now, go ahead and work the pads out of the caliper carrier. Go ahead and push the other one out. There you go.

Now, pop these little steel shims off of the carrier. You'll want to be careful not to bend those or make them break. Sometimes it helps to use a small flat blade screwdriver. Pop them out. Okay, just work them carefully so you don't bend them or make any kinks. Look them over, and make sure that they aren't all rusty, that there isn't a whole lot of buildup, or that they look brittle and breakable. Clean all that debris off of both sides of the steel shims with a steel brush. Make sure that there's no dirt or buildup on there that's going to cause them to sit uneven once we reinstall them onto the caliper carrier.

Now, clean the surface where it's going to sit back into the carrier. Same thing, you don't have to make them shine, just make sure that you remove all the heavy buildup and debris. Now, you want to carefully line this up, and pop back into place. You'll feel it snap when it seats in all the way. If you're confused about which way it goes in you can always use the other side for reference that's why we remove them one at a time. Go ahead and pop this one off and clean it up the same way. Yeah, that's upside down. That’s why we leave the other side on for reference. Now that it's all cleaned up and we have some new grease on our slides, our caliper carriers are ready to go back on the car.

Now, we're going to show you how to make sure that the new parts that you bought from 1AAuto.com match up to the parts that we removed from our vehicle and how to diagnose what might be going wrong with your brake system. First off, we want to make sure that our rotors are the same size and that we have the same bolt pattern on them. It's very important that you check here that these are vented. That means you can see we have two flat surfaces here with these slotted spots on the inside, which allows heat to escape from these rotors. The other thing we'll want to check. We can see that our paths are the exact same size here. Obviously, the new ones are going to be a little bit thicker, but they're same size, same shape, so they should fit in just right.

Now, take the second and see what might've gone wrong with our old brakes here. You can see that this one being the inboard pad, we can tell that from the fact that there's a little bit of a piston mark here on backing plate. All that rust and corrosion that you cleaned off of the caliper carrier could have been holding up this pad while this one was still being pushed easily by the piston, causing this to wear out while this pad didn't take as much of the abuse.

There's all kinds of little stuff that can keep your car from operating properly. That's why we're so careful about cleaning stuff when we put it back together. It looks like everything matches up, and it's going to go in just like our original equipment, right? Looks that way to me. Let' get it back on the car.

All right. All this corrosion and buildup on hub surface might make it so that our rotor doesn't sit on level, and it can cause some crunching noises, and maybe a little bit of vibration. That it can make it hard for us to remove the rotor the next time we have to do our brakes. Let's go ahead and take a steel brush and clean up this surface here where you can see the buildup where our rotor is going to sit over the center more and flat surfaces as well.

All right. Again, we don't have to make this super clean, shiny, make it look like new. Just want to make sure that we get all that heavy buildup off so our rotor sits on their nice and flat. To ensure that none of that nasty rust and corrosion comes back, we're going to apply a thin coat of brake grease to the surface of the hub. Both the flat portions here and this center where the bore of our rotor wheel sit.

What's the bore?

The bore is that hole in the center of the rotor, as well as if you flip the wheel over the hole behind the center cap which sits here to help center the rotor and the wheel when we bolt them on. Though you're probably ready to slap that rotor onto the hub, but you're actually going to want to install it backwards with this face touching the hub first. Spray it down with some brake cleaner.

Why are we doing this?

When they store these rotors in warehouses and factories, they coat it in a thin layer of cosmoline, which is a material that keeps this steel from rusting or corroding while the parts of being stored.

Do I just do the outside?

We're going to do the flat surface here where our brake pad rides, as well as this inner portion, because our parking brake sits inside the rotor instead of being a cable part of the caliper. Go ahead and flip the rotor around. When you reinstall it, make sure that this doubled hole here lines up with those threads so we can reinstall the screw for our rotor. Go ahead and clean down that front surface as well. Let's go ahead and reinstall that screw in here. Don't need the ratchet for this, you can just go ahead and sue the extension in the driver to start it off.

Make sure that our rotor sits straight up and down when we reinstall our pads. How tight should this be? Just get it as tight as you can go using the extension and driver without a ratchet. Now, we're going to take our break caliper carrier that we've cleaned and greased and our two 18mm bolts. Reinstall it onto the spindle.

How's this go?

These are the threaded holes where our bolts are going to sit in. We need this channel here to ride over the rotor. These are different lengths. I didn't notice that when they came out. What you're going to want to do is check where it goes through the spindle. As you can see the top here is thicker than the bottom, so we'll use our longer bolt in the top.

Cars often have different length hardware even on the same components, so always be sure to check the lengths of your hardware; but in the chance you miss something, try to inspect the part, and look for differences in the thickness of materials to account for the different lengths of the bolts.

Once you've gotten them as tight as you can by hand, snug them up a ratchet and an 18mm socket. Then we'll show you how to tighten them down properly with a torque wrench. Now, we're going to use a torque wrench to tighten the bolts to spec.

What does that mean exactly?

When the manufacture designs some of these parts, they have a certain tightness or the amount of tension in mind for the bolts. This can vary on the type of materials it uses, and the forces that act against it, as well as the actual construction being size and diameter of the bolt. To make sure that we use the right amount of force to tighten it, we have a special calibrated tool here called a torque wrench that measures the amount of force we use to tighten the bolt to make sure the torque wrench knows how tight we want the bolt.

We'll loosen this lock at the bottom by turning it counterclockwise. Rotate this drum on the handle clockwise until we have 88. To set this to 88, once we've loosed our lock we'll want to make sure that the top edge of this drum lines up to the 80 mark and then we get the 8 to match up the vertical line. Here we can see at zero that this top edge of the drum lines up to the bottom of the horizontal line at 80. We'll keep rotating it until our 8 lines up the vertical lines.

Tighten up our lock. Now, when you tighten those two bolts, you'll feel it click that let you know that they're tight enough. That's the click to us know that the bolt is torqued to spec. To make sure that our pads slide nice and smooth in the caliper carrier. We’re going to want to grease these points here, but, to reduce mess, go ahead and put some grease on the tip of your finger; grease these parts here where it's going to ride in the caliper slides. Now, line up those tabs.

Set it in straight and slide it until it touches the rotor. Now, do the same thing for the pad in the rear. Now, to make sure that our caliper slides smoothly onto the pads and doesn't make any kind of noise or friction, we're going to want to put a thin coat of that brake grease here on the backing for both the outboard and inboard pad.

Go ahead and undo the bungee cord so you can free up the caliper and bring it out here where we can work on it. Again, anytime we're moving the caliper be careful for that rubber hose. Now, we'll use a pair of groove lock pliers to collapse the piston. You'll want to grab a fixed point on the back of the piston and the face the piston itself. Slowly squeeze in to compress it.

These can get a little sticky and take some force, so just be careful that if you have to squeeze hard it's nowhere where it's going to break a tab or slide off and cause a danger to yourself.

We want to reinstall the caliber onto the carrier. As you can see here, it bumps into the slides a little bit, so you'll have to push those in and set the caliper over them. Once you've got it into place, go ahead and start your two 13mm bolt by hand. Now, go ahead and tighten them up with a 13mm socket and ratchet. Once they're snug, we'll torque them with a torque wrench. Now that we've gotten those tightened down by hand, go ahead and torque those to 44 ft-lbs.

You're going to have to reinstall the wheel and tire. Once you've got the lugs as tight as you can with vehicle off the ground, go ahead and put the weight of the vehicle back onto it by lowering it off the jack and jack stands so we can tighten it up with a torque wrench.

Now, you're going to want to torque your lug nuts to 100 ft-lbs. Be sure when you're tightening down your lug nuts that you always tighten them down in a cross pattern. We want to make sure that when we tighten the lug nuts down that we always skip one. This means that our wheel gets tighten down onto the hub evenly and prevents it from being tighten down crooked if we were to go to circle, which can make tire off-center, causing vibration and some of the lug nuts to not be properly torqued, meaning that we could even have the wheel fall off.

Matt what did you think of doing your first job?

You know, it wasn't that bad. It's pretty easy.

You have fun?

Yeah, it was pretty cool.

Doing these kinds of repairs at home can save you a lot of money and give you the confidence of knowing what's going on under your vehicle when you're driving it. Now, we're going to go ahead and match up the other side because you always want to do your brake pads and rotors in pairs. Wait, I'll get this one.

Thanks for tuning in. We hope this video helped you out. Next time you need parts for your car, please visit 1AAuto.com. Also check out our other helpful how-to and diagnosis videos.