Diesel Service Technician or Mechanic

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.

Duties

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.

Work Environment

Diesel service technicians and mechanics held about 293,200 jobs in 2021. The largest employers of diesel service technicians and mechanics were as follows:

Truck transportation 20%
Wholesale trade 13
Local government, excluding education and hospitals         9
Automotive repair and maintenance 8
Self-employed workers 8

Diesel technicians usually work in well-ventilated and sometimes noisy repair shops. They occasionally repair vehicles on roadsides or at worksites.

Injuries and Illnesses

Diesel service technicians and mechanics often lift heavy parts and tools, handle greasy or dirty equipment, and work in uncomfortable positions. Sprains and cuts are common among these workers. Diesel technicians need to follow some safety precautions when in the workplace.

Work Schedules

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.

Education and Training

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.

Education

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.

Training

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.

Personality and Interests

Diesel service technicians and mechanics typically have an interest in the Building and Organizing interest areas, according to the Holland Code framework. The Building interest area indicates a focus on working with tools and machines, and making or fixing practical things. The Organizing interest area indicates a focus on working with information and processes to keep things arranged in orderly systems.

If you are not sure whether you have a Building or Organizing interest which might fit with a career as a diesel service technician and mechanic, you can take a career test to measure your interests.

Diesel service technicians and mechanics should also possess the following specific qualities:

Customer-service skills. Diesel mechanics frequently talk to their customers about automotive problems and work that they have planned, started, or completed. They must be courteous, good listeners and ready to answer customers’ questions.

Dexterity. Mechanics need a steady hand and good hand-eye coordination for many tasks, such as disassembling engine parts, connecting or attaching components, or using hand tools.

Mechanical skills. Diesel mechanics must be familiar with parts and components of engines, transmissions, braking mechanisms, and other complex systems. They must also be able to disassemble, work on, and reassemble parts and machinery.

Troubleshooting skills. Diesel mechanics must be able to identify mechanical and electronic problems, make repairs, and offer a proper maintenance strategy. They must be familiar with electronic control systems and the appropriate tools needed to fix and maintain them.

Pay

The median annual wage for diesel service technicians and mechanics was $48,690 in May 2021. 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 $35,730, and the highest 10 percent earned more than $76,150.

In May 2021, 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          $60,670
Wholesale trade 55,940
Automotive repair and maintenance 47,630
Truck transportation 47,120

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.

Job Outlook

Employment of diesel service technicians and mechanics is projected to grow 4 percent from 2021 to 2031, about as fast as the average for all occupations.

About 28,500 openings for diesel service technicians and mechanics are projected each year, on average, over the decade. Many of those openings are expected to result from the need to replace workers who transfer to different occupations or exit the labor force, such as to retire. 

Employment

As more freight is shipped across the country, additional diesel-powered trucks will be needed to carry freight wherever trains and pipelines are not available or economical. In addition, aging vehicles with diesel engines are likely to require more maintenance and repair, supporting the need for diesel technicians.

For More Information

For more information about careers and education for diesel service technicians and mechanics, visit

Association of Diesel Specialists

National Automotive Technicians Education Foundation

For more information about certification, visit

National Institute for Automotive Service Excellence

 

 

FAQ

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The career information above is taken from the Bureau of Labor Statistics Occupational Outlook Handbook. This excellent resource for occupational data is published by the U.S. Department of Labor every two years. Truity periodically updates our site with information from the BLS database.

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