Brake condition decides safety for every long run. No driver should overlook this pre-departure check on the tractor head brake system.
Fire up the engine and keep an eye on the air gauge. Wait for air pressure to build to the normal working level. If it takes too long to fill, or cannot reach the required reading, do not leave. Check the air compressor and pipe connections for leaks. Once pressure is ready, turn the engine off. Hold the service brake pedal for roughly one minute. Quick pressure loss means leaking hoses, fittings or brake chambers.
Drain water from each air tank through the drain cock. Water trapped inside damages the air dryer and causes rust in the whole air circuit. Walk around and check all rubber hoses. Look for cracks, rub marks and oil wet spots. Test the low air alarm light and buzzer to make sure they trigger when pressure drops too low. Operate the parking brake a few times. It should hold firmly and release cleanly without jamming.
Crawl under the unit to check slack adjusters and push rods. Too much push rod travel, worn brake linings or cracked drums need repair before travel. Connect the trailer air lines and test the tractor protection valve. Press the brake pedal to confirm trailer brakes activate at the same time. ABS lights should run self-check and go out once finished.
Try braking at low speed on level ground. The tractor must stop straight without drifting left or right. Weird noise, laggy brake response or uneven braking cannot be ignored. Brake faults will get worse on the road. A careful check before you go keeps you and your load safe over long distances.
