Commercial drivers must ensure brakes are properly adjusted, with the mark-and-measure method being the most reliable for measuring brake stroke. This involves marking the pushrod, applying the brakes, and measuring the stroke to ensure it doesn’t exceed the chamber’s adjustment limit. Other methods, like measuring free stroke or using parking brakes, are less reliable and may give false readings. Mark-and-measure at full pressure is the best way to ensure proper adjustment.


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Notice: CTT 2025

When coupling a trailer, inspect the area, check trailer ID, inspect the kingpin, ensure 5th wheel lock is open, and chock wheels. Reverse carefully, confirm coupling by tug test, inspect lock engagement, raise landing gear, connect lines, and inspect the trailer. To uncouple, park on level ground, lower landing gear, unlock 5th wheel, disconnect lines, deflate suspension, pull forward, check support, then drive off.

The ZF 12-speed gearbox peripheral parts disassembly involves 11 main tasks, including removing the speed sensor harness, gearbox control device, breather bolt, gear selection and sensor modules, valve body, contact, output shaft speed sensor, odometer sensor, retarder, and PTO. Various tools like torque wrenches, sockets, and special pins are used.

Proper disassembly and assembly of truck gearboxes requires clean conditions, careful sequencing, and attention to alignment. Always follow outside-to-inside principles, handle parts gently, and avoid forcing components. Common issues like gear misalignment or incomplete assembly can be avoided with proper technique. Understand each step—especially for oil pump, auxiliary box, and middle housing—to ensure smooth and safe maintenance.

Discover 10 fascinating truck facts: from the 80m-long French road train to the world's fastest jet-powered truck. Learn how Mercedes got its name, why Arctic vehicles stay unlocked, and why China's a top buyer of seatbelt buckles. The first truck appeared in 1896, and one had wiring over 1800m long. Fun fact: the first driver was a woman! Trucks are complex machines with high recycling value after retirement.