Although most diesel technicians learn on the job after a high school education, employers are increasingly preferring applicants who have completed postsecondary training programs in diesel engine repair. In addition, obtaining industry certification may be helpful because certification demonstrates a diesel technician’s competence and experience.
Most employers require a high school diploma or equivalent. High school or postsecondary courses in automotive repair, electronics, and mathematics provide a strong educational background for a career as a diesel technician.
Some employers prefer to hire workers with postsecondary education in diesel engine repair. Many community colleges and trade and vocational schools offer certificate or degree programs in diesel engine repair.
These degree programs mix classroom instruction with hands-on training and include learning the basics of diesel technology, repair techniques and equipment, and practical exercises. Students also learn how to interpret technical manuals and electronic diagnostic reports.
Diesel technicians who begin working without any postsecondary education are trained extensively on the job. Trainees are assigned basic tasks, such as cleaning parts, checking fuel and oil levels, and driving vehicles in and out of the shop.
After they learn routine maintenance and repair tasks and demonstrate competence, trainees move on to more complicated subjects, such as vehicle diagnostics. This process can take from 3 to 4 years, at which point a trainee is usually considered a journey-level diesel technician.
Over the course of their careers, diesel technicians must learn to use new techniques and equipment. Employers often send experienced technicians to special training classes conducted by manufacturers and vendors to learn about the latest diesel technology.
Licenses, Certifications, and Registrations
Certification from the National Institute for Automotive Service Excellence (ASE) is the standard credential for diesel and other automotive service technicians and mechanics. Although not required, this certification demonstrates a diesel technician’s competence and experience to potential employers and clients, and often brings higher pay.
Diesel technicians may be certified in specific repair areas, such as drivetrains, electronic systems, and preventative maintenance and inspection. To earn certification, technicians must have 2 years of work experience and pass one or more ASE exams. To remain certified, diesel technicians must pass a recertification exam every 5 years.
Many diesel technicians are required to have a commercial driver’s license so that they may test-drive buses and large trucks.
Customer-service skills. Diesel technicians frequently discuss automotive problems and necessary repairs with their customers. They must be courteous, good listeners, and ready to answer customers’ questions.
Detail oriented. Diesel technicians must be aware of small details when inspecting or repairing engines and components, because mechanical and electronic malfunctions are often due to misalignments and other easy-to-miss causes.
Dexterity. Mechanics need a steady hand and good hand–eye coordination for many tasks, such as disassembling engine parts, connecting or attaching components, and using hand tools.
Mechanical skills. Diesel technicians must be familiar with engine components and systems and know how they interact with each other. They often disassemble major parts for repairs, and they must be able to put them back together properly.
Organizational skills. Diesel technicians must keep workspaces clean and organized in order to maintain safety and accountability for parts.
Physical strength. Diesel technicians often lift heavy parts and tools, such as exhaust system components and pneumatic wrenches.
Troubleshooting skills. Diesel technicians use diagnostic equipment on engine systems and components in order to identify and fix problems in mechanical and electronic systems. They must be familiar with electronic control systems and the appropriate tools needed to fix and maintain them.
The median annual wage for diesel service technicians and mechanics was $48,500 in May 2019. The median wage is the wage at which half the workers in an occupation earned more than that amount and half earned less. The lowest 10 percent earned less than $31,990, and the highest 10 percent earned more than $74,090.
In May 2019, the median annual wages for diesel service technicians and mechanics in the top industries in which they worked were as follows:
|Local government, excluding education and hospitals||$57,940|
|Automotive repair and maintenance||46,320|
Many diesel technicians, especially those employed by truck fleet dealers and repair shops, receive a commission in addition to their base salary.
Most diesel technicians work full time. Overtime is common, as many repair shops extend their service hours during evenings and weekends. In addition, some truck and bus repair shops provide 24-hour maintenance and repair services.
What Diesel Service Technicians and Mechanics Do
Diesel service technicians and mechanics (also known as diesel technicians) inspect, repair, or overhaul buses and trucks, or maintain and repair any type of diesel engine.
Diesel service technicians and mechanics typically do the following:
- Consult with customers, read work orders, and determine work required
- Plan work procedures, using technical charts and manuals
- Inspect brake systems, steering mechanisms, transmissions, engines, and other parts of vehicles
- Follow checklists to ensure that all critical parts are examined
- Read and interpret diagnostic test results to identify mechanical problems
- Repair or replace malfunctioning components, parts, and other mechanical or electrical equipment
- Perform basic care and maintenance, including changing oil, checking fluid levels, and rotating tires
- Test-drive vehicles to ensure that they run smoothly
Because of their efficiency and durability, diesel engines have become the standard in powering trucks and buses. Other heavy vehicles and mobile equipment, including bulldozers and cranes, also are powered by diesel engines, as are many commercial boats and some passenger vehicles and pickups.
Diesel technicians make major and minor engine repairs, and work on a vehicle’s electrical and exhaust systems to comply with pollution regulations.
Diesel engine maintenance and repair is becoming more complex as engines and other components use more electronic systems to control their operation. For example, fuel injection and engine timing systems rely on microprocessors to maximize fuel efficiency and minimize harmful emissions. In most shops, workers often use hand-held or laptop computers to diagnose problems and adjust engine functions.
Diesel technicians also use a variety of power and machine tools, such as pneumatic wrenches, lathes, grinding machines, and welding equipment. Hand tools, including pliers, sockets and ratchets, and screwdrivers, are commonly used.
Employers typically provide expensive power tools and computerized equipment, but workers generally acquire their own hand tools over time.
Technicians and mechanics who work primarily on automobiles are described in the profile on automotive service technicians and mechanics.
Technicians and mechanics who work primarily on farm equipment, construction vehicles, and railcars, are described in the profile on heavy vehicle and mobile equipment service technicians.
Technicians and mechanics who work primarily on motorboats, motorcycles, and small all-terrain vehicles are described in the small engine mechanics profile.