Peterbilt Truck 379

Build up air pressure in the system to the governor cut-out point

Release the parking brakes (push in the yellow knob)

Rate of air pressure drop. The rate of drop should not be more than 2 psi (14 kPa) per minute

Start the engine and build up the air pressure again

Stop the engine. Ensure that the parking brakes are still released (i.e., the yellow knob is pushed in)

Rate of air pressure drop registered by the air gauge. The rate of drop should not be more than 3 psi (21 kPa) per minute

Replace brake lining as required

Check the control arm for cracks

Sign off on the brake system maintenance

Check clutch pedal shaft for excessive looseness

Upload a photo of the clutch pedal shaft

Check clutch release linkage for excessive looseness

Upload a photo of the clutch release linkage

Lubricate clutch release bearing

Upload a photo of the lubricated clutch release bearing

Upload a photo of the lubricated clutch release shaft

Sign off on the clutch maintenance

Warning: Clutch adjustment should be done by a trained certified mechanic

Enter the clutch pedal free travel measurement

Does the vehicle have automatic clutch adjustment?

If the vehicle doesn't have automatic clutch adjustment, report to a trained certified mechanic

Sign off on the clutch pedal adjustment

Check warning lights in light bar at the ignition start position to verify bulbs function

Check power supply harness for worn or damaged insulation, corroded terminals, frayed wires, and oil or fluid leaks on the connectors or wiring

Sign off on the electrical system check