Drum Brake System: Adjustments

Rear brakes should be adjusted after rear brake service or before adjusting parking brake. These brakes have self-adjusting shoe mechanisms that ensure correct brake lining-to-drum clearances at all times. The automatic self-adjusting mechanism operates whenever the parking brake lever is applied on all models except the Duo-servo type. On Duo-servo type, the self-adjusting mechanism operates when the brakes are applied as the truck is moving rearward.