K 3500 Truck 4WD V8-454 7.4L VIN J SFI (1996)
Brake Bleeding: Service and Repair
Four Wheel Anitlock Brake System
Two Person Procedure (Preferred)
BLEEDING PROCEDURES
Important: Never pump the brake pedal. Fluid cavitation may occur.
NOTICE: Gravity and vacuum bleeding are not recommended for this ABS system.
Two Person Procedure (Preferred)
1. Raise the vehicle to gain access to the system bleed screws. Install clear tubing on the bleed screws so that air bubbles in the fluid can be seen.
2. Begin by bleeding the system at the right rear wheel, then the left rear, right front and left front.
3. Open one bleed screw at a time 1/2 to 1 full turn.
4. Slowly depress the brake pedal until it reaches its full travel and hold until the bleed screw has been tightened. Release the brake pedal and wait
10-15 seconds for the master cylinder to return to the home position.
Important: Repeat steps 1 through 4 until approximately 1 pint of brake fluid has been bled from each wheel. Clean brake fluid should be present at
each of the wheel bleed screws. Check the master cylinder fluid level every 4 to 6 strokes of the brake pedal to avoid running the system dry.
5. If any component is replaced which may have caused air to enter the BPMV, use a Scan Tool to run "Function Test" four times while applying the
brake pedal firmly.
Important: Set the park brake when running the "Function Test."
6. Rebleed all four wheels using steps 1 through 4 to remove the remaining air from the brake system.
7. Evaluate the brake pedal feel before attempting to drive the vehicle and rebleed as many times as necessary to obtain appropriate pedal feel.
Pressure Bleeding (Low Pressure)
Pressure Bleeding (Low Pressure)
1. Install pressure bleeder per instructions.
2. Install combination valve depressing tool J391 77 if the vehicle is equipped with the metering portion of the combination valve. Remove both dust
caps on the combination valve. Install the tool on the end of the combination valve with a brass center pin.
3. Bleed all four wheels beginning at the right rear wheel, then the left rear, right front and left front. Leave the bleed screws open until 1 pint of fluid
has been bled out of each wheel.
4. After bleeding all four wheels1 remove the combination valve clip. Use a Scan Tool to run 4 functional tests while applying the brake pedal
firmly.
5. Repeat steps 1 through 3 then evaluate the pedal feel.
6. Rebleed the wheels as many times as necessary to obtain good pedal feel before attempting to drive the vehicle. A good bleed will use
approximately 2 to 3 quarts of brake fluid.
Important: Never reuse brake fluid after it has been bled through a brake system.
