Diesel Mechanics

• Nature of the Work

  Diesel engines are more durable and heavier than gasoline engines. In addition, they are more fuel efficient than gasoline engines, in part because the higher compression ratios found in diesel engines help convert a higher percentage of the fuel into power. Because of their greater durability and efficiency, diesel engines are used to power most of the Nation's heavy vehicles and equipment.

  Diesel mechanics repair and maintain diesel engines that power transportation equipment, such as heavy trucks, buses, and locomotives; construction equipment such as bulldozers, cranes, and road graders; and farm equipment such as tractors and combines. A small number work on diesel-powered automobiles. Diesel mechanics also service a variety of other diesel-powered equipment, such as electric generators and compressors and pumps used in oil well drilling and irrigation systems.

  Most diesel mechanics work on heavy trucks used in industries such as mining and construction to carry ore and building materials, and by private and commercial trucking lines for general freight hauling. Most light trucks are gasoline powered, and although some diesel mechanics may occasionally service gasoline engines, most work primarily on diesel engines. (For information on mechanics who work primarily on gasoline engines, see the Handbook statement on automotive mechanics.)

  Mechanics who work for organizations that maintain their own vehicles may spend much time doing preventive maintenance to assure safe operation, prevent wear and damage to parts, and reduce costly breakdowns. During a maintenance check on a truck, for example, they usually follow a regular checklist that includes the inspection of brake systems, steering mechanisms, wheel bearings, and other important parts. They usually repair or adjust a part that is not working properly. Parts that cannot be fixed are replaced.

  In many shops, mechanics do all kinds of repairs, working on a vehicle's electrical system one day and doing major engine repairs the next. In some large shops, mechanics specialize in one or two types of work. For example, one mechanic may specialize in major engine repair, another in transmission work, another in electrical systems, and yet another in suspension or brake systems.

  Diesel mechanics use a variety of tools in their work, including power tools such as pneumatic wrenches to remove bolts quickly; machine tools such as lathes and grinding machines to rebuild brakes and other parts; welding and flame-cutting equipment to remove and repair exhaust systems and other parts; common handtools such as screwdrivers, pliers, and wrenches to work on small parts and get at hard-to-reach places; and jacks and hoists to lift and move large parts. Diesel mechanics also use a variety of testing equipment, including ohmmeters, ammeters, and voltmeters when working on electrical systems and electronic components; and tachometers, dynamometers, and engine analyzers to locate engine malfunctions.

  For heavy work, such as removing engines and transmissions, two mechanics may work as a team, or a mechanic may be assisted by an apprentice or helper. Mechanics generally get their assignments from shop supervisors or service managers, who may check the mechanics' work or assist in diagnosing problems.

• Working Conditions

  Diesel mechanics usually work indoors, although they may occasionally make repairs on the road. They are subject to the usual shop hazards such as cuts and bruises. Mechanics handle greasy and dirty parts and may stand or lie in awkward or cramped positions to repair vehicles and equipment. Work areas usually are well lighted, heated, and ventilated, and many employers provide locker rooms and shower facilities.

• Employment

  Diesel mechanics held about 250,000 jobs in 1994. Nearly one-quarter serviced trucks and other diesel-powered equipment for customers of vehicle and equipment dealers, leasing companies, and independent automotive repair shops. Over one-fifth worked for local and long-distance trucking companies, and nearly one-seventh maintained the buses and trucks of buslines, public transit companies, school systems, and Federal, State, and local government. The remainder maintained the fleets of trucks and other equipment of manufacturing, construction, and other companies. A relatively small number were self-employed.

  Diesel mechanics are employed in every section of the country, but most work in towns and cities where trucking companies, buslines, and other fleet owners have large repair shops.

• Training, Other Qualifications, and Advancement

  Although many persons are able to qualify for diesel mechanic jobs through years of on-the-job training in related, lesser skilled positions, training authorities recommend that persons seeking diesel mechanic jobs complete a formal diesel mechanic training program. Diesel technology is becoming more sophisticated and diesel engines increasingly use electronic components to control a growing variety of functions. Knowledge of basic electronics is becoming essential for diesel mechanics to diagnose whether a malfunction is caused by an electronic component or whether it can be traced to another source. Most employers prefer to hire graduates of formal training programs in diesel mechanics, and completion of such a program can speed advancement to the journey mechanic level. These 1- to 2-year programs, given by vocational and technical schools and community and junior colleges, lead to a certificate of completion or an associate degree. They provide a foundation in the basics of the latest diesel technology and electronics, and enable trainees to more quickly master the service and repair of the actual vehicles and equipment encountered on the job.

  A formal 4-year apprenticeship is another good way to learn diesel mechanics. However, apprenticeships are becoming less common because employers are reluctant to make such a long-term investment in training, especially when graduates of postsecondary diesel mechanic programs are increasing in number. Competition for the limited number of apprenticeship slots is often extremely keen. Typical apprenticeship programs for diesel truck and bus mechanics consist of approximately 8,000 hours of practical experience working on transmissions, engines, and other components and at least 576 hours of formal instruction to learn blueprint reading, mathematics, engine theory, and safety. Frequently, these programs include training in both diesel and gasoline engine repair.

  Even though most employers prefer to hire graduates of formal post secondary training programs in diesel mechanics, the number of persons who complete such programs are too few to meet their needs. As a result, many diesel mechanics still learn their skills on the job. Unskilled beginners usually do tasks such as cleaning parts, fueling, lubricating, and driving vehicles in and out of the shop. As beginners gain experience and as vacancies become available, they usually are promoted to mechanics' helpers. In some shops, beginners—especially those having automobile service experience—start as mechanics' helpers.

  Most helpers can perform routine service tasks and make minor repairs after a few months' experience. They advance to increasingly difficult jobs as they prove their ability. After they master the repair and service of diesel engines, they learn to work on related components such as brakes, transmissions, or electrical systems. Generally, at least 3 to 4 years of on-the-job experience is necessary to qualify as an all-round diesel truck or bus mechanic. Additional training on other components, such as hydraulic systems, may be necessary for mechanics who wish to specialize in other types of diesel equipment.

  For unskilled entry level jobs, employers generally look for applicants who have mechanical aptitude and are at least 18 years of age and in good physical condition. Completion of high school is required by a growing number of employers. Courses in automotive repair, electronics, English, mathematics, and physics provide a good basic educational background for a career as a diesel mechanic. Good reading and basic mathematics skills are needed to study technical manuals to keep abreast of new technology and learn new service and repair procedures and specifications. A State commercial driver's license is needed for test driving trucks or buses on public roads. Practical experience in automobile repair in a gasoline service station, in the Armed Forces, or as a hobby also is valuable.

  Employers sometimes send experienced mechanics to special training classes conducted by truck, bus, diesel engine, parts, and equipment manufacturers where they learn the latest technology or receive special training in subjects such as diagnosing engine malfunctions. Mechanics also must read service and repair manuals to keep abreast of engineering changes.

  Voluntary certification by the National Institute for Automotive Service Excellence (ASE) is recognized as a standard of achievement for diesel mechanics. Mechanics may be certified as Master Heavy- Duty Truck Technician or may be certified in one or more of six different areas of heavy-duty truck repair: brakes, gasoline engines, diesel engines, drive trains, electrical systems, and suspension and steering. For certification in each area, mechanics must pass a written examination and have at least 2 years of experience. High school, vocational or trade school, or community or junior college training in gasoline or diesel engine repair may substitute for up to 1 year of experience. To retain certification, mechanics must retake the tests at least every 5 years.

  Most mechanics must buy their own handtools. Experienced mechanics often have thousands of dollars invested in tools.

  Experienced mechanics who have leadership ability may advance to shop supervisors or service managers. Mechanics who have sales ability sometimes become sales representatives. A few mechanics open their own repair shops.

• Job Outlook

  Employment of diesel mechanics is expected to increase about as fast as the average for all occupations through the year 2005. Because this is a large occupation, more job openings are expected for diesel mechanics than for most other occupations. Although employment growth will create many new jobs, most job openings will arise from the need to replace diesel mechanics who transfer to other fields of work or retire or stop working for other reasons.

  Employment of diesel mechanics is expected to grow as freight transportation by truck increases. More trucks will be needed for both local and intercity hauling due to the increased production of goods. Additional diesel mechanics will be needed to repair and maintain growing numbers of buses and heavy construction graders, cranes, earthmovers, and other equipment. Due to the greater durability and economy of the diesel relative to the gasoline engine, buses and trucks of all sizes are expected to be increasingly powered by diesels, also creating new jobs for diesel mechanics.

  Careers in diesel mechanics are attractive to many because wages are relatively high and skilled repair work is challenging and varied. Opportunities should be good for persons who complete formal training in diesel mechanics at community and junior colleges and vocational and technical schools, but others may face competition for entry level jobs.

• Earnings

  According to a survey of workplaces in over 160 metropolitan areas, diesel mechanics earned median earnings of $14.61 an hour in 1993. The middle 50 percent earned between $12.00 and $17.49 an hour. However, earnings may vary by industry and by geographic location.

  Beginning apprentices usually earn from 50 to 75 percent of the rate of skilled workers and receive increases about every 6 months until they complete their apprenticeship and reach the rate of skilled mechanics.

  The majority of mechanics work a standard 40 hour week, although many work as many as 70 hours per week, particularly if they are self employed. Those employed by truck and bus firms which provide service around the clock may work evenings, nights, and weekends. They usually receive a higher rate of pay for this work.

  Many diesel mechanics are members of labor unions, including the International Association of Machinists and Aerospace Workers; the Amalgamated Transit Union; the International Union, United Automobile, Aerospace and Agricultural Implement Workers of America; the Transport Workers Union of America; the Sheet Metal Workers' International Association; and the International Brotherhood of Teamsters.

• Related Occupations

  Diesel mechanics repair trucks, buses, and other diesel-powered equipment and keep them in good working order. Related mechanic occupations include aircraft mechanics, automotive mechanics, boat engine mechanics, farm equipment mechanics, mobile heavy equipment mechanics, and motorcycle mechanics and small-engine specialists.

• Sources of Additional Information

  More details about work opportunities for diesel mechanics may be obtained from local employers such as trucking companies, truck dealers, or bus lines; locals of the unions previously mentioned; or the local office of the State employment service. Local State employment service offices also may have information about apprenticeships and other training programs.

  For general information about careers as truck, bus, and diesel mechanics, write to:
  Automotive Service Industry Association, 25 Northwest Point, Elk Grove Village, IL 60007-1035.

  American Trucking Associations, Inc., Maintenance Council, 2200 Mill Rd., Alexandria, VA 22314-4677.

  For a directory of accredited private trade and technical schools with training programs for diesel mechanics, contact:
  Accrediting Commission of Career Schools and Colleges of Technology, 2101 Wilson Blvd., Suite 302, Arlington, VA 22201.

  National Automotive Technicians Education Foundation, 13505 Dulles Technology Dr., Herndon, VA 22071-3415.

  For a directory of public training programs for diesel mechanics, contact:
  Vocational Industry Clubs of America, P. O. Box 3000, 1401 James Monroe Highway, Leesburg, VA 22075.

  Information on how to become a certified heavy-duty diesel mechanic is available from:
  ASE, 13505 Dulles Technology Dr., Herndon, VA 22071-3415.

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