One of the most important safety features on your car are the brakes. Let's find out how to replace your rear brake pads, so you can stop safely.
Introduction
I tend to keep cars for a very long time – often for a decade or more. Of the four vehicles in my family, three have been with us for at least ten years. I also don't enjoy paying someone else to do something I know that I can do myself. So I've spent many a Saturday morning cross-legged in my driveway, up to my elbows in brake dust replacing brake pads.
Simple brake maintenance is one of the easiest jobs a car owner can do. With a little patience, the right tools, and a tolerance for getting a pair of pants dirty, you can do it, too.
On most cars, the front brakes are noticeably larger in diameter than the rear brakes, since a vehicles' momentum shifts the load of the vehicle forward under braking. However, the rear brakes are crucial for ensuring safe and smooth stopping. Because they are smaller than the front brakes, they can wear more quickly than the front brakes on some vehicles. Replacing the rear brake pads when they wear is a critical part of safe braking and saving on bigger repair costs down the road.
Also, always replace the brake pads on both sides of the vehicle at the same time. Brake pads are packaged in sets to complete one axle (front or rear) anyhow, so you've already bought the parts to do both sides. Replacing pads on only one side of the vehicle can lead to increased brake wear, as well as potentially imbalanced braking performance.
Tools Required
- Assortment of sockets or wrenches or ratchets to remove the brake caliper
- Brake caliper wind-back tool – for some cars; a c-clamp or large pair of pliers will work but check a service manual first
- Floor jack – or the emergency jack from the car's on-board tool kit
- Gloves
- Impact wrench or ratchet or breaker bar to fit the wheel lug socket
- Jack stands
- Safety glasses
- Small bungee cord or old coat hanger or mechanic's wire or a dedicated brake caliper hanging tool
- Small pry bar or flat-headed screwdriver
- Socket to fit wheel lugs – or the lug wrench from the car's on-board tool kit
- Torque wrench
- Wheel chocks
- Wire brush
Materials Required
- Brake cleaner solvent
- Brake parts grease
- Paper towels or shop towels
- Replacement brake pads with the included steel brake retainer clips
Project step-by-step (10)
Step 1
Remove The Rear Wheel
Start the process by placing wheel chocks in front of the front wheels. (Don’t set the emergency brake; engaging makes removing the calipers harder.)
Set the jack in place and lift just enough to put some pressure on the jack. Use a lug wrench, socket and ratchet, or impact wrench to loosen the lug nuts on the wheel. Lift the vehicle until the wheel comes off the ground, then spin the lug nuts off the lugs and remove the wheel.
Step 2
Remove Bolts From Caliper Slider Pins
Loosen the bolts holding the caliper in place with either a box-end wrench or a socket and ratchet. Remove the bolts and use a mechanic’s wire or a short bungee cord to hang the caliper up and away from the work area to avoid putting tension on the brake line. Sometimes, the caliper can be challenging to remove – in this case, use a small pry bar or flat-headed screwdriver to carefully lever the brake caliper away from the brake disc.
Step 3
Remove Bolts From Caliper Brackets
Use a box-end wrench or socket and ratchet to loosen the two bolts holding the caliper bracket in place. You may need a longer-handled wrench to get more torque on reluctant bolts. If you don’t have one handy, slip a length of pipe over the box-end wrench handle to fashion an extension. Remove the bolts and lift the caliper bracket free from the rotor and wheel hub.
This is a good time to inspect the condition of the brake rotors. Now that the entire surface of the brake rotors is visible, inspect them for rust or grooves. If they are badly worn or suspect, it may be the time to replace those, too.
Step 4
Lubricate Caliper Slider Pins
As long as you have removed the caliper, take the time to lubricate the two caliper slider pins. Wipe each off with a clean rag and brake cleaner solvent, then brush with brake parts grease. Replace them in their sockets and twist them to distribute the lubricant.
Step 5
Remove The Brake Pads
Slide the brake pads out of the caliper bracket. Pull the old stainless steel retainer clips free from the grooves that hold them in place, paying attention to their orientation (snap a quick picture if you think you might forget), and then clean the dust off the bracket using a wire brush and brake cleaner solvent.
Step 6
Reattach Caliper Bracket
Set the bracket into position and twist the two anchor bolts with your fingers until snug. Tighten each firmly with a long-handled box-end wrench. Be careful not to over-torque and strip the threads.
Step 7
Seat The Brake Pads
Snap the new retainer clips into place, positioning them the same way as the old ones. Apply a thin coat of brake parts grease to the inside of each clip holding the brake pad ears. Some new pads will even include a small packet of this grease.
Find the new brake pad with the metal flange attached to its back. This flange is the squealer that signals heavy pad wear and should be mounted on the inside pad. Slide this pad into the clip-lined grooves in the caliper bracket with the friction material facing the rotor. Fit the matching outer pad into the other side of the bracket, again with the friction material facing the rotor.
Step 8
Reattach Caliper
Retract the brake piston within the brake caliper. If the piston face is hollow, any tool large enough to compress the piston will suffice, taking care not to break through the thin metal that comprises the back face of the piston. You can protect the piston by laying one of the old pads across it as you push it back. Many newer models require a special tool called a brake caliper wind-back tool. Identify these pistons by looking for a solid surface (not hollow) on the piston face that has two or three recesses for the winding pins to grip and turn.
If you get the brakes pulled apart and don’t have the tool, you can still complete the job with a needle-nose vise-grip wrench or pliers. Grip the piston face with the tip of the wrench and turn it clockwise to retract the piston.
Reposition the caliper, fitting it over the new brake pads. Insert the anchor bolts through the caliper and into the slider pins. Finger-tighten until snug, then tighten each firmly with a box-end wrench.
Step 9
Re-mount The Wheel
Seat the wheel on the lugs and thread the nuts onto the lugs using your fingers. Rather than working around the hub in a circle, work in a star pattern, jumping across the hub to ensure the wheel is tightened evenly against the hub. Once all the lugs are threaded, snug them by hand before tightening them firmly with a lug or impact wrench, again working in that same star pattern. Make a point of rechecking the lugs after driving your vehicle for a few days – preferably with a torque wrench.
Repeat the process on the other side of the vehicle.
Safely lift the vehicle from the jack stand, remove the jack stand, and lower the vehicle to the ground.
Step 10
Pump The Brake Pedal
After installing the wheels, make sure to pump the brake pedal to reengage the caliper piston to the brake pads. Failure to do so will result in no brakes when the pedal is pushed the first time.
