For 1990-2009 cars only
- Apply the parking brake.
- Block the wheels.
- Run the engine in order to fully charge the air system.
- Turn off the engine.
- Drain the air pressure from the supply reservoir. Refer to Draining Reservoirs .
- Have an assistant apply and release the brake pedal two times.
- Verify the front and rear slack adjusters move smoothly and promptly.
- Start the engine.
- Charge the system air pressure to the governor cut-out point.
- Remove the wheel blocks.
Important: Applying and releasing the brakes repeatedly drains the supply reservoir pressure. This can eventually cause the brakes to appear sluggish.
| • | Replace the in-line check valve (10) at the front service reservoir if the front brakes are sluggish or fail to move. |
| • | Replace the in-line check valve (10) at the rear service reservoir if the rear brakes are sluggish or fail to move. |
