Are you hearing a nasty screech when you press the brake pedal in your car? Does it sound like rock monsters are playing the world’s loudest frame of bowling every time you need to slow down? Well, it may be time to change your brakes. Here’s how.
This story was originally published on November 5, 2014
A car’s braking system is one of the most important components in your driving experience, as it’s the only thing keeping you from smashing into that bus full of nuns on your spirited run to the grocery store. It’s a fairly simple hydraulic system that allows the force applied at the pedal to be translated to clamping force at the wheel. Here’s how it works:
When a brake pad wears down on a rotor, it will often make a squeaking sound when applied. This is an audible safety measure to make sure that the driver knows to change the brakes soon. Unfortunately, some pads don’t do this particularly well, so newer cars have brake pad wear sensors installed as part of their system, alerting the driver on the dash that the pads needs replacement. In addition, when a brake pad gets low, it will require a longer stroke of the caliper’s piston to clamp down on the rotor, therefore lowering the amount of fluid in your brake reservoir. If the pads are low, you’ll be able to see a noticeable change in your brake fluid’s level, and may even get a “BRAKE” warning light on the instrument cluster.
If all these signs are ignored, the pad’s material will wear down to the point where the only thing making contact with the rotor surface is the pad’s metal backing plate, which is made of steel, and it will make heavy grooves in your rotor’s surface, forcing you to replace the rotors as well.
A typical brake pad job on a regular commuter/non-performance car costs around $50-$80 for all four sets of pads, and about $150-$200 for a set of pads and rotors, front and rear. Labor an an independent shop should be around 1-2 billable hours , so by doing it yourself, you’re saving around $180.
Note: The procedure listed below was performed on a 2007 Scion tC, but it should be similar in nearly any car with 1 or 2 piston calipers and rotors. If you’re unsure, please consult your car’s factory service manual.
You can perform a brake service on a car with regular hand tools, in your driveway or garage. Here’s how to do it:
Step 1: Acquire Tools
- 3/8" Ratchet
- 1/2" Ratchet
- 1/2" Breaker Bar
- 3/8" Assorted extensions
- 3/8" Sockets, assorted
- 1/2" Sockets, Assorted
- Open-ended wrenches, assorted
- Torx sockets, assorted (Used mainly on German and some American cars)
- Hex sockets, assorted (Used mainly on German and some American cars)
- Reverse Torx sockets, assorted (Used mainly on German and some American cars)
- Hydraulic Jack
- Jack Stands
- Pry Bar
- Wire Brush
Step 2: Buy Brake Pads And Rotors
With brake pads, ceramic tends to be the best, as they give the best brake feel and the longest protection against brake fade, although dust may accumulate on your wheel a bit more than conventional pads. You can look for pads for your car here.
As far as rotors, unless you’re using the car on a track, any cheap rotor will do, but beware - the rotor manufacturers on some of the cheaper examples don’t have the greatest quality control, and it may be necessary to mill the rotors after you receive them due to vibration when braking. Personally, I’d go for Brembo rotors. They have great quality control and fit/finish for the price. You can also find pad and rotor sets here.
Step 3: Loosen Lugs
In order to get the best purchase on the front lug nuts, engage the parking/emergency brake (if none is available/not working, put a brick behind the back wheel) put your 1/2" breaker bar on the appropriate socket size (usually 17-21mm) and turn counter-clockwise with the car on he ground. Remember, you’re loosening, NOT removing. Get the lugs loose enough that you’ll be able to take them off with a regular ratchet. When working on the rear, put bricks behind the front wheels and engage the parking brake to give yourself the best chance of removing the lug nuts. Release the parking brake when the wheel is off.
Step 4: Raise Car
Put the hydraulic jack underneath either the car’s frame rail or factory jacking points on the side of the car. These can usually be seen as the dimpled pieces of protruding metal on the bottom of the car. Some German cars have black rubber pads that serve as the jacking points.
Place jack stands underneath the car, rest car on jack stands, making sure that its weight cannot shift. You can now remove the wheels. Now is also a great time to clean your wheels of all brake dust. I used a Wagner Steam Cleaner and some Simple Green degreaser:
Step 5: Loosen Caliper
There should be 2 12mm or 14mm bolts on the caliper. Remove them and the caliper should be able to slide out. If te caliper doesn’t slide out easily, use a pry bar or flat head screwdriver and pry it out.
Rest the caliper on the suspension, or use zip-ties or a bungee to secure it to a place where it can’t hang. Don’t put any strain on the brake line.
Step 6: Remove Caliper Carrier
Remove the 2 17mm or 19mm bolts on the rear of the hub that keep the caliper carrier on. These are on tight, so use a breaker bar with a mallet or an impact gun if you can.
Step 7: Remove Rotor
Give the rotor a few good whacks with a hammer and it should come out. Please note that some rotors have a locating screw that would need to be removed for the rotor to come out. Also, on older cars, rust may be an issue, so instead of beating it with a hammer, there may be threaded holes that you can force bolts through and release the caliper that way. You should end up with this:
Step 8: Install New Rotor
Before installing the new rotor, use a wirebrush and take off the rust on the hub, to prevent corrosion in the future. You can also use WD-40 on this part. When installing the rotor, to have it sit flush, use a lug nut and an open-ended wrench to secure it while tightening down the rest of the components. Also use brake cleaner or a degreaser to wipe off the oily packing residue from the rotor.
Step 9: Assemble Carrier
Replace the carrier bolts and tighten them down using an impact gun or breaker bar.
Step 10: Compress Caliper
Using the C-Clamp and one of the old brake pads, compress the caliper piston until the piston is flush with the housing of the caliper. Make sure to have the cap off the brake reservoir, as you don’t want to risk blowing a line.
Step 11: Install Pads and Caliper
Install pads in the carrier and use a little bit of anti-squeal grease on the outside of the pad to ensure smooth operation. Install the caliper bolts and ensure that the caliper moves without binding. Tighten the bolts and double check your work.
Step 12: Put On Wheels.
Tighten the lugs hand tight when in the air, and torque them down when the wheels are on the ground using a torque wrench or breaker bar.
Step 13: Repeat For All 4 Wheels
Step 14: Pump Brakes Until Pressure Is Reached
You should feel pressure within 3 pumps of the pedal.
Step 15: Break In Pads and Braking System
The brakes may squeal or make some noise during the first few miles. This is normal. To break in the new components, on a highway, accelerate to 60 MPH, and gradually slow to 40, and repeat a few times, then 50-30 MPH a few times. Then simply drive normally, and listen for any odd noises. If all is well, you just replaced your brakes. Job done!
Tavarish is the founder of APiDA Online and writes about buying and selling cool cars on the internet. He owns the world’s cheapest Mercedes S-Class, a graffiti-bombed Lexus, and he’s the only Jalopnik author that has never driven a Miata. He also has a real name that he didn’t feel was journalist-y enough so he used a pen name and this was the best he could do.