Truck and transport mechanics inspect, repair and maintain commercial trucks, emergency vehicles, buses and road transport vehicles. In some jurisdictions, they may also work on commercial trailers and recreation vehicles.

They work on the structural, mechanical, electrical and electronic vehicle systems and components such as engines, cab, chassis and frames, brakes, steering, suspension, drive train, HVAC (heating, ventilation and air conditioning), fuel systems and hydraulic systems. In addition, truck and transport mechanics perform preventative maintenance and diagnosis of vehicles. Truck and transport mechanics use specialized tools including hand tools, test meters, hoisting and lifting equipment, staging equipment, welding and cutting equipment, hydraulic equipment, safety equipment, recycle and recovery equipment, and complex electronics and computer diagnostic test equipment.

Truck and transport mechanics are employed in the agricultural, construction, mining, forestry, petrochemical and transportation sectors. They may be employed in small repair shops, motor vehicle dealers, large fleet maintenance companies, public transportation companies, government highway departments, railways and construction companies.

Smaller companies routinely require that truck and transport mechanics perform a wide variety of tasks. Those who work in larger shops may specialize in some of the following areas: engine and fuel systems, transmission systems, HVAC systems, steering, alignment, brakes, drive lines, suspension, hydraulics, electrical and electronic systems, truck-trailer repair or diagnostic services.

Work environments for truck and transport mechanics differ from one job to another. The mechanic frequently works in awkward positions, and must often climb, stoop, crouch and kneel. They also must handle heavy parts and tools.

There is some risk of injury involved in working with heavy equipment and power tools. Common occupational hazards are exposure to chemicals and harmful materials, repetitive motion, noise, sharp edges and heavy equipment.

Key attributes for people entering this trade are mechanical aptitude, manual dexterity, good hand-eye coordination, strength, stamina and agility. They must also have a good understanding of computerized machinery, good problem-solving and analytical skills, and the ability to read and understand service manuals. Good communication skills and patience are also important. Other assets are good vision, hearing and sense of smell to diagnose problems. This analysis recognizes similarities or overlaps with the work of automotive service technicians, agricultural equipment technicians, heavy duty equipment technicians, recreation vehicle service technicians and transport trailer technicians.

With experience, truck and transport mechanics act as mentors and trainers to apprentices in the trade. They may also advance to supervisory, service manager and training positions.