Tools Required

J 28434 Bleeder Wrench

Deplete the booster reserve by applying the brakes several times with the engine off until all reserve is depleted.

Notice: Avoid spilling brake fluid on any of the vehicle's painted surfaces, wiring, cables or electrical connectors. Brake fluid will damage paint and electrical connections. If any fluid is spilled on the vehicle, immediately flush the area with water to minimize the potential for damage.

1. Fill the master cylinder reservoir to the full level mark using only Delco Supreme II Brake fluid, or equivalent DOT-3 brake fluid, as specified in General Information.

•	Maintain the fluid level in the reservoir during bleeding.

•	Have an assistant press the brake pedal, when needed, during bleeding.

Important: Be sure the master cylinder reservoir cap is installed before the brake pedal is pressed. This prevents brake fluid from spraying from the reservoir.

2. If the master cylinder is known or suspected to have air in the bore, bleed it as follows before bleeding the calipers.

•	Loosen the forward brake pipe connection at the master cylinder.

•	Allow brake fluid to flow from the connector port. Maintain the reservoir fluid level.

•	Tighten the forward brake pipe on master cylinder.

Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

•	Depress the brake pedal slowly one time and hold. Loosen forward the brake pipe connection again to purge air from the bore. Tighten the connection and then slowly release the brake pedal. wait 15 seconds. Repeat the sequence, including the 15 second wait, until all air is removed from the bore.

Tighten
Tighten the brake pipe connection to 33 N·m (24 lb ft).

•	Repeat step 2 and bleed the master cylinder at the rear connection.

3. Bleed the individual wheel calipers only after all air is removed from the master cylinder. If you know that the calipers do not contain air, then do not bleed them.
4. If the wheel circuits have be to bled, use the following sequence: right rear, left rear, right front, left front.
5. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
6. Remove the bleeder valve cap and place the proper box-end wrench, or J 28434 over the bleeder valve.
7. Attach a transparent tube to the bleeder valve; submerge the other end of the tube in a clear container, partially filled with clean brake fluid.
8. Depress the brake pedal slowly once and hold. Use slow pedal action. Rapid pedal pumping pushes the master cylinder secondary piston down the bore in a way that makes it difficult to bleed the system.

•	Loosen the bleeder valve to purge air from the caliper.

•	Tighten the bleeder valve, and slowly release the brake pedal.

•	Wait 15 seconds, then repeat the sequence, including the 15 second wait, until all air is removed. you might have to repeat the sequence 10 or more times to remove all the air.

Tighten
Tighten the caliper bleeder valve to 13 N·m (115 lb in).

9. Install the bleeder cap valve caps.
10. Lower the vehicle.
11. Fill the master cylinder to the full mark.
12. Check the brake pedal for "sponginess." Repeat entire bleeding procedure to correct "sponginess."
13. When manual bleeding is completed, pressure bleed the brake system using a Scan Tool. Refer to Antilock Brake System Automated Bleed Procedure in Antilock Brake System.