Diesel Mechanic
Diesel mechanics service and repair the engines and heavy systems in trucks, buses, mining equipment and farm machinery, keeping fleets working.
- Median salary*
- $80,600
3.9%vs last year, before tax
- People employed
- 8,900
0.0%vs last year
- Projected growth*
- +5%
to 2035
- AI exposure*
- Moderate
- automation risk
- Average hours*
- 42/wk
+2h vs all jobs
- Shortage status*
- In shortage
national
Most diesel mechanics work in a workshop, though field service roles take them to mine sites, depots and farms when a machine can't be moved. The trade sits close to motor mechanics, but the engines are larger, the vehicles are heavier and the diagnostic software is specific to each manufacturer. Their work keeps freight, construction and mining fleets moving, so breakdowns tend to set the pace of the day.
How much do diesel mechanics earn?
The median full-time salary for a diesel mechanic is $80,600 per annum, before tax, up $16,700 since 2018.
Where you work moves pay more than anything else: mine site and field service roles usually sit above general workshop positions, and roster or shift arrangements add penalties and allowances on top of the base rate. Qualified tradespeople earn more than apprentices and assistants, and some employers pay extra for additional licences such as a heavy vehicle licence or a high risk work licence. Dealership and fleet work tends to be steadier, while breakdown and callout work trades predictability for higher rates.
What does a diesel mechanic do day to day?
The list below is what fills most weeks; the exact mix shifts with seniority and whatever stage the current work is at.
- Running manufacturer diagnostic software to trace faults in engine, electrical and hydraulic systems
- Servicing diesel engines, transmissions, brakes, steering and suspension on trucks, buses and heavy equipment
- Removing and overhauling engine assemblies, then refitting and testing them
- Road testing vehicles and machines after repair and completing roadworthy or site inspections
- Writing up service records, ordering parts and explaining repair options and costs to owners and fleet managers
What skills do diesel mechanics need?
Employers look for installation and maintenance, hand and power tool work, plant and equipment operation, backed by Cummins INSITE fluency and strong problem solving.
Specialist skills
- Installation and maintenance
- Hand and power tool work
- Plant and equipment operation
- Regulatory compliance
Software and tools
- Cummins INSITE
- Cat ET (Caterpillar Electronic Technician)
- Jaltest
- Snap-on diagnostic software
- Detroit Diesel Diagnostic Link
General skills
- Problem solving
- Attention to detail
- Safety and compliance awareness
Is the job growing?
About 8,900 people work as diesel mechanics in Australia, and employment is projected to grow 5% over the decade to 2035. That's modest growth: demand is steady rather than booming.
How do you become a diesel mechanic?
Here's the path most diesel mechanics take, step by step.
- 1Finish school with reasonable maths and English
Most people enter through an Australian Apprenticeship, and employers generally look for Year 10 or Year 12 completion with passes in maths and English. A pre-apprenticeship course in automotive can help if you are competing for a placement.
- 2Start a Certificate III apprenticeship
The trade qualification is a Certificate III in Heavy Commercial Vehicle Mechanical Technology (AUR31120) or a similar automotive course, delivered through an Australian Apprenticeship that usually runs about four years. You are paid while you train, splitting your time between a workshop and TAFE.
- 3Add the licences and site inductions your workplace needs
A car licence is the minimum, since road testing is part of the job, and a heavy vehicle licence opens up more work. Mining and construction sites require their own inductions and medicals, and the requirements differ between states and employers.
- 4Build manufacturer and diagnostic training on top
Cummins, Caterpillar and Detroit Diesel each run courses on the diagnostic platforms used in their engines, and employers hiring for dealership or fleet work value them. This training is also how you move toward specialist and field service roles.
Ready to apply as a diesel mechanic?
Whether you're working toward becoming a diesel mechanic or already are one and want a hand with the next step (sharpening your resume for ATS screening, tightening your cover letter, or knowing what you'll actually be asked at interview), here are examples grounded in this specific role, not generic templates.
What jobs can a diesel mechanic move to?
Moving into Auto Electrician typically comes with the biggest pay rise, worth $65,400 a year more on average.
| Move to | Typical pay change | Overlap | Retraining |
|---|---|---|---|
| Auto Electrician Diesel engine electrical and diagnostic skills transfer to auto electrical work, with further study in the auto electrical trade. | +$65,400 | 67% | reskill |
| Marine Engine Driver Diesel engine knowledge suits marine vessels, and a short maritime course qualifies the mechanic to operate marine engines. | +$18,200 | 83% | short course |
| Motor Mechanic Light vehicle repair is an adjacent trade, and diagnostic skills transfer with retraining in petrol and light vehicle systems. | +$3,700 | 50% | reskill |
| Agricultural Mechanic Heavy diesel and hydraulic skills carry into farm machinery repair, with further training in agricultural mechanical systems. | −$5,200 | 67% | reskill |
| Marine Mechanic Marine mechanic work uses similar diesel engine repair skills, with additional training in marine propulsion and vessel systems. | −$5,200 | 63% | reskill |
Moves are chosen from Jobs and Skills Australia's Data on Occupation Mobility, which follows income tax records between 2011-12 and 2020-21, together with entry requirements and skill overlap. A known move is one people were seen making in that data. Pay change compares median full-time pay for the two roles.
Who works as a diesel mechanic?
The typical diesel mechanic is 32 years old; 99% are men, 94% work full-time, and full-timers average 42 hours a week.
- 32
- Median age
- 1%
- Female share
- 94%
- Full-time
- +2h
- vs all-jobs avg
What's it like being a diesel mechanic?
The rhythm of the job is set by the fleet: scheduled servicing in the workshop, then breakdowns and field callouts that can push a shift late. Most of the day is physical and noisy, spent on your feet around hot, greasy machinery, with diagnostic software doing more of the thinking than it used to. People who enjoy it tend to like working through a fault methodically and seeing a machine leave the workshop running properly.
What people like
- The fault you finally pin down. Intermittent wiring and hydraulic problems can take several visits to solve, so finding the cause feels like a real result rather than a routine repair.
- Finished work you can point to. At the end of a long job there is a rebuilt engine or a truck heading back out on the road, and the customer drives it away.
- Variety across machines and industries. One week it might be a prime mover, the next a haul truck, an excavator or a harvester, and the skills carry across because the diesel systems are related.
- A trade that holds up anywhere. Diesel mechanics work in transport, mining, farming, marine and construction, so the qualification can move with you to a regional town or a different industry.
What people find hard
- Grit, heat and heavy components. You spend the day on concrete around hot exhausts, diesel and grease, lifting and manoeuvring parts that are genuinely heavy.
- Callouts that ignore the clock. Breakdowns happen when they happen, so field service and fleet roles can mean night work, weekend callouts or rosters away from home.
- Tools come out of your own pocket. Most mechanics build up their own hand tool kit during the apprenticeship, and a decent set is a real cost early on.
- Explaining cost to someone already losing money. When a truck is off the road the owner is watching lost income, and quoting a major engine repair is often the hardest conversation in the job.
Based on our synthesis of professional-body surveys and public accounts of the role, not first-person verified reviews.
Which industries employ diesel mechanics?
Other Services employs the largest share of diesel mechanics, followed by Transport, Postal and Warehousing.
Top employing industries
- 1Other Services
- 2Transport, Postal and Warehousing
- 3Wholesale Trade
- 4Manufacturing
- 5Mining
Ranked by employment share; the source doesn't publish an exact percentage per industry.
| Certificate III/IV | 34% | |
|---|---|---|
| Diploma / Advanced Diploma | 26% | |
| Bachelor degree | 20% | |
| Year 12 or below | 20% |
Will AI replace diesel mechanics?
This is a moderate-exposure trade. Diagnostic fault finding is where technology reaches furthest, with code readers and manufacturer platforms such as Cummins INSITE and Cat ET suggesting likely causes and job management software handling records and quotes. The physical work of removing, rebuilding and testing engines and heavy components stays with the mechanic, which is what keeps the overall exposure from being higher.
Share of typical working time by exposure level
- Engine, transmission and hydraulic repairRemoving, overhauling and refitting heavy components in tight spaces is physical work that no current system performs.35%low
- Fault finding and planning the repairCode readers and diagnostic software narrow down likely causes, but confirming a fault that only appears under load still comes down to the mechanic.25%moderate
- Scheduled servicing and inspectionsFluid changes, brake and suspension checks and roadworthy inspections are hands-on, though the records are increasingly logged digitally.25%low
- Parts ordering, service records and customer quotesParts catalogues, job management systems and quoting tools already handle much of this, so the time it takes keeps shrinking.15%high
Moves least exposed to AI
These career moves from diesel mechanic work are rated low for AI exposure:
- Auto Electrician
High skill overlap (67%), reskill to get there, and a low automation-risk profile.
- Marine Engine Driver
High skill overlap (83%), short course to get there, and a low automation-risk profile.
- Agricultural Mechanic
High skill overlap (67%), reskill to get there, and a low automation-risk profile.
Common questions about becoming a diesel mechanic
Straight answers to the questions people ask most.
How much does a diesel mechanic earn?
Full-time diesel mechanics earn a median of $80,600 per year before tax. Pay depends heavily on setting, with mine site, field service and dealership roles usually above general workshop work, and shift or roster arrangements adding penalties and allowances. It is a median figure, so individual earnings vary with location, employer and experience.
How do you become a diesel mechanic?
You complete a Certificate III apprenticeship, usually about four years, which combines paid workshop work with TAFE study. Employers generally ask for Year 10 or Year 12 with reasonable maths, and a pre-apprenticeship course can improve your chances of being taken on. Once qualified, you can add manufacturer diagnostic training or a heavy vehicle licence.
Are diesel mechanics in demand?
Diesel mechanics are currently in shortage nationally, and employment is projected to grow 5% over the decade to 2035. The trade is tied to transport, mining, farming and construction, so how much work is available in your area tends to follow the activity in those industries.
Will AI or automation replace diesel mechanics?
The hands-on side of the job is not going anywhere soon. Diagnostic software and code readers already suggest likely faults, and job management systems handle records and quotes, but removing, rebuilding and testing engines and heavy components is still manual work. Exposure is moderate: the tools are changing how faults are found, not who carries out the repair.
What can a diesel mechanic move into?
The closest sideways move is motor mechanic work, with pay $3,700 more and a lot of shared diagnostic skill. Marine engine driver roles pay $18,200 more after a short maritime course, while agricultural mechanic and marine mechanic roles are open with further training in those systems. Many experienced mechanics end up running their own workshop, mobile service van or field service business, which is often where earnings grow.
Do diesel mechanics need their own tools?
Most employers expect you to bring your own hand tools, and mechanics typically build a set up during the apprenticeship. Specialist diagnostic equipment such as code readers and laptop software usually belongs to the workshop, and some employers offer a tool allowance or supply a full kit.
Related roles
- Auto Electrician
- Marine Engine Driver
- Agricultural Mechanic
- Marine Mechanic
- Motor Mechanic
- Mechanic's Assistant
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