How to Clean Car Brakes

It's not uncommon to have to clean and adjust certain types of cars that have enclosed rear drum brakes. Brake dust from the shoes is entrapped inside the drum and often gets stuck between the friction surface of the shoes and the inside diameter of the drum causing annoying squeals when braking. It's not a bad idea to clean and lube front (or rear) disc brakes from time to time, but rarely performed between pad replacement procedures.

Instructions

1

Lift the car safely and securely in the lift. Put on the safety glasses. Remove the rear lug nuts and wheels with the gun and a socket.

2

Determine the drum application on the vehicle. Some drums come off by hand, some are retained by screws on the drum face, some have small disposable ring retainers on one or more lug studs. Remove any drum retaining devices and remove the drum. Put off the face mask before proceeding. In some cars, you may have to shock the drum from the hub of the vehicle by striking the face of the drum near the outer edge. Some may have interior ridges where de-adjusting the brake shoes (with a small flathead screwdriver and a shoe brake spoon) will help to get the drum lip from getting caught on the friction material of the shoe. There are also some drums that are attached to the rear spindle that require removing the dust cap, removing the spindle nut cover and cotter pin, removing the spindle nut and washer, and then pulling the drum and outer bearing out. In some rare occasions, the drums come right off in your hands.

3

Empty the contents of the brake dust into a rear brake dust cleaner or parts cleaner. Handle with caution as it contains asbestos particles. Spray the entire exposed rear brake assembly with brake clean spray to eliminate the caked up brake dust covering the components (with a drain bucket below preferably). Use a pneumatic blow gun to blow the excess dust and debris from the rear brake assembly. Some OSHA regulations would require having the rear brake assembly covered to contain the asbestos contaminants, but hardly any repair facilities have them or use them if they do.

4

Clean the drum in the parts cleaner machine to remove the dust and dirt from the inside. Chipping the rust ridges from some drums helps to prevent rust rubbing noises against the backing plate when the wheel is in motion.

5

Remove the rear shoes or manipulate them forward to apply a light coat of silicone brake lubricant to the shoe contact points on each shoe. Use an acid brush to spread the lubricant if you do not remove the shoes. If you do remove the shoes, use the die grinder and reconditioning disc to clean the contact points and then apply the lubricant. Replace the shoes.

6

Replace the drums in the same fashion you removed them and readjust the rear shoes as necessary. Replace the wheels and lug nuts and torque the lug nuts to proper vehicle specifications.

How to Clean Car Disc Brakes

7

Put on the safety glasses. Remove the lug nuts and wheels from the front or rear tires to clean the disc brakes using the pneumatic gun and a socket. Remove the two caliper bolts or slide bolts using the gun or a socket and ratchet. In some cases, the upper and lower bolts are different so determine this and establish a relationship between the bolt and its position in the caliper. Pry the caliper from the rotor using a pry bar or screwdriver. Support the caliper to the chassis of the vehicle with a bungee cord to not allow it to dangle from the brake hose.

8

Remove the brake pads. In some calipers, the pads are clipped to the caliper itself and will come off when you pry it from the rotor. In other cases, the pads remain intact with the caliper anchor hugging the rotor. In any application, remove the pads and again, establish a relationship between the pad and its position to the caliper and rotor.

9

Remove the two caliper bridge bolts (if applicable) using either the gun or the ratchet and a socket. Take the caliper anchor (if applicable) to a bench vise and lock it in place to work on it. Remove the thin metal rattle clips or hardware and clean them using a die grinder and reconditioning disc. Clean both the upper and lower sides. Clean the surface of the caliper anchor where the rattles clips or hardware sit against the anchor as well. Do both upper and lower contact points and hardware. Apply a coat of silicone brake lubricant to the contact point of the anchor then place the hardware or rattles clips on top and secure them. Place another coat of lubricant on top of the hardware or rattle clip and set the anchor aside. In some applications, the caliper anchor is actually an extension of the knuckle and does not come off. In this case, clean the contact points with the die grinder in the same fashion and apply lubricant, but you'll have to do it right on the car instead of at the bench vise.

10

Spray the exterior and interior of the rotor with brake clean spray and allow to air dry. It will very quickly. Replace the caliper anchor and bolts and tighten. Replace the pads in the anchor.

11

Bring the caliper pins and or slide bolts (if necessary) to the bench grinder with a wire brush wheel and clean off any excess lubricant or corrosion on the slides or bolts on the surface of the wire brush wheel. Set the bolts or slides aside.

12

If necessary attach the caliper honer to the die grinder and hone the caliper slide/bolt holes. Compress the caliper piston using a large C-clamp and place over the rotor. Apply a coating of silicone brake lubricant to the caliper slides/bolts and reinsert into the caliper and tighten.

13

Replace the wheel and lug nuts and torque them to proper vehicle specifications. Remember to pump the foot brake pedal to restore the hydraulic pressure back to the compressed caliper pistons.