Parking Brake Does not Hold

Summit Utilatruck Gen 1

This article covers Service Bulletin (SB16-005) of the procedures required for proper adjustment of the parking brake system. As there are multiple adjustments within the system, it is important to follow the steps in the prescribed order.

Start Adjustment

Star1

1. With vehicle on a level surface and the power off, block the front wheels so that the unit will not roll in either direction.

2. Release the parking brake.

3. With floor jack, raise rear of vehicle until both rear wheels are off the ground.

4. Place stands under chassis of vehicle to provide safety and stability while working on unit.

5. Remove both rear wheels and set aside.

Star2

6. The brake shoes are adjustable through access slot in drum. Note: this can also be accomplished by removing drum, adjusting star, and then replacing the drum.

7. Turn the shoe adjuster star until the drum is no longer free turning. Then, slightly back off the adjuster enough to enable the wheel to turn freely again.

8. Repeat for other side.

Equalizer Adjustment

Equil1

1. With the parking brake pedal still disengaged, check equalizer behind the accelerator/brake cluster. Adjust the nut so that there is no slack in any of the three cables.

Parking Brake Cluster Adjustment

Clevis3

1. Verify that the parking brake pedal engages the parking brake properly at three clicks of the pedal. If it does not, the clevis will an adjustment in the parking brake pedal cluster.

2. To adjust parking brake pedal, remove the display panel to access the assembly.

Clevis1

3. Remove the pin from the clevis. Rotate the clevis so that it engages the brakes at three clicks of the pedal and, when released, the rear wheels still spin. Then, tighten the locking nut on the back of the clevis.

Hydraulic Brake Adjustment

Hydo1

1. Lastly, if the service brake pedal at rest is not all the way up in the released position; adjust the clevis at the end of the master cylinder rod to raise the pedal. Remove the pin from the clevis, spin the clevis so that it allows the pedal to fully release at rest and the rear wheels still spin. Then, tighten the locking nut on the back of the clevis.

2. Reassemble vehicle including display panel and wheels. Remove floor stands and lower unit to the ground.

3. Verify that the vehicle rolls freely without the brake applied.

4. Verify that with the parking brake pedal engaged with three clicks, the vehicle holds position.