The master cylinder is a vital part of the braking system. This device is responsible for sending the necessary hydraulic fluid through your brake lines and powering your calipers when you apply the brakes. The master cylinder is easy to maintain, as all you have to do is make sure the fluid is topped off and clean.
Set the parking brake on your truck. Chock the wheel to prevent the truck from rolling.
Open the hood. The master cylinder is the yellow case on the right side along the firewall.
Unbolt the cylinder from the hydraulic booster. There are two bolts to unscrew.
Pull the master cylinder from under the hood. You will spill some brake fluid.
Bolt the new master cylinder in its place. The cylinder should mount right up.
Unscrew the cap on top of the cylinder. Pour to the fill line with DOT 3 brake fluid. Make sure you put the cap back on the master cylinder.
Bleed the brake system with the help of a partner. The brake bleeder valve is located on the brake caliper.
Jack the car up and remove a front wheel.
Loosen the round-shaped valve on the top of the caliper. It will only require a couple of turns to loosen.
Instruct a helper to pump the brake pedal to release any air in the line. When fluid spurts out of the valve, the helper can tighten the valve. The helper will need to pump the pedal until the pedal is stiff (no free play).
Loosen the valve with your 7/16 wrench and instruct your helper to pump the pedal until fluid is released. Tighten the valve. Repeat these steps until all the air is released from the brake line.
Repeat these steps on the other front wheel. Your brake pedal should have little free play. Bleeding the brake line should also relieve the "spongy" feel of the brake pedal.
Fill the master cylinder to the fill line after bleeding the brakes. You will lose some fluid as you bleed the system.
