Diesel Mechanic Apprentice Hub
Diesel mechanics (often called heavy vehicle mechanics or diesel fitters) keep trucks, buses, earthmovers and farm machinery running. You diagnose faults, service engines, air brakes, transmissions, hydraulics and electrical systems, then repair or replace what is worn out. The gear is big, the torque figures are big, and the stakes are big: if a road train or a haul truck is parked up, someone is losing serious money every hour.
It is a four year apprenticeship in most cases, done on the job with an employer while you knock over your Certificate III at TAFE or another training provider. The trade splits into a few worlds: truck and transport workshops, mining and heavy mobile plant, and agriculture and machinery dealers. All of them are short of good people, and the mining side is one of the best paid trades in the country once you are qualified.
Thinking about it?
Thinking about getting into Diesel Mechanic?
How to get in with no experience
The standard path is a four year apprenticeship: you get hired by a workshop (truck dealer, transport fleet, plant hire, mining contractor or ag dealer) or by a group training organisation that places you with one, sign a training contract, and complete the AUR31120 Certificate III in Heavy Commercial Vehicle Mechanical Technology (or AUR31220 Mobile Plant Technology for the earthmoving side) through TAFE or another RTO while you work. You can start straight from school, through a school based apprenticeship in years 11 and 12, or as an adult career changer, and a pre apprenticeship certificate helps you stand out but is not compulsory. Once you finish, you are a qualified heavy vehicle mechanic or diesel fitter and the whole transport, ag and mining world opens up.
Who it suits
It suits people who like big machinery, real problem solving and physical work, and who do not mind getting properly dirty. You need patience for diagnosis (modern gear is as much electronics as steel), the discipline to follow safety procedures around equipment that can kill you, and the resilience for early starts, breakdown call outs and seasonal or roster driven hours. If you want the mining money you also need to be honest with yourself about FIFO life: rosters away from home are not for everyone. It is a poor fit if you want clean hands, fixed office hours or hate paperwork, because job cards and service records are part of the trade.
What you can earn
The Australian Government's Your Career profile for diesel motor mechanics lists average weekly earnings of about $1,405 (roughly $73,000 a year) for the occupation overall, and figures like that are an average across all settings, so check the live figure on the profile. The spread around it is wide: metro truck workshops sit near the average, while heavy diesel fitters on mining sites, particularly FIFO roles under enterprise agreements, are among the best paid tradespeople in the country, with job ads routinely advertising packages well above the occupation average. Overtime, shift loadings, site allowances and being on call move the number a long way in this trade. Apprentice pay is a separate system set by your award or agreement, apprenticeship year and age: work your own rate out with the Fair Work Pay and Conditions Tool rather than trusting anyone's quoted figure.
Job outlook
Demand is strong and consistent. The Jobs and Skills Australia profile shows around 7,400 employed diesel motor mechanics with a stable future demand rating, but that understates it: automotive trades have sat on the national Occupation Shortage List year after year, employers in transport, agriculture and mining all report trouble finding qualified people, and the occupation is on the skilled migration lists because local supply is short. Freight volumes keep growing, mining fleets keep expanding, and machinery keeps getting more complex, which pushes work toward properly trained technicians. Qualified diesel mechanics also branch into fitter roles, workshop supervision, maintenance planning, field service, OEM technical roles and mine maintenance leadership, so the trade is a launch pad, not a dead end.
Earnings and outlook are a guide only and change over time. Sources: Your Career: Diesel Motor Mechanic occupation profile (opens in a new tab), Jobs and Skills Australia: Diesel Motor Mechanics (ANZSCO 321212) (opens in a new tab), Jobs and Skills Australia: Occupation Shortage List (opens in a new tab), Fair Work Pay and Conditions Tool (opens in a new tab), Rio Tinto Future Skills: Apprentice heavy duty diesel fitter (opens in a new tab)
Start with these
What apprentices actually do
- •Service and maintain diesel engines in trucks, buses, plant and machinery: oils, filters, coolant, belts and inspections
- •Diagnose faults using scan tools, multimeters, pressure gauges and their own ears and eyes
- •Repair and overhaul engines, turbochargers, fuel systems, cooling systems and exhaust and emission systems
- •Work on drivelines: clutches, manual and automatic transmissions, diffs, tailshafts and final drives
- •Maintain and repair air brake systems, steering and suspension on heavy vehicles
- •Repair hydraulic systems on tippers, cranes, loaders and farm machinery: pumps, rams, hoses and valves
- •Carry out electrical work: batteries, starters, alternators, wiring and the electronic control systems that now run everything
Same trade, different worlds
Same trade, very different day depending on the kind of work your employer does.
Transport and truck workshops
Dealer workshops (Kenworth, Volvo, Scania, Isuzu and the rest), fleet workshops for transport companies, bus depots and independent truck shops. This is the classic heavy vehicle world: prime movers, trailers, rigids and buses.
- •Scheduled servicing and breakdown repairs on trucks and buses, often against tight deadlines because the truck has freight booked
- •Lots of air brake, driveline, suspension and engine work, plus more electronics every year
- •Shift work and on call breakdown roadside call outs are common in fleet and dealer jobs
- •Usually paid under the Vehicle Repair, Services and Retail Award unless the workshop has an enterprise agreement
- •Good grounding for your whole career: transport workshops teach you speed, diagnosis and dealing with customers
Mining and heavy plant (including field service and FIFO)
Mine sites, quarries, civil construction and the OEM dealers that support them (Caterpillar, Komatsu, Hitachi, Liebherr dealers and contractors). The machines are huge: haul trucks, excavators, dozers, loaders and drills. Many roles are FIFO or DIDO on a roster.
- •Work is usually planned maintenance in a workshop on site, plus field service out on the pit floor in all weather
- •FIFO rosters (for example two weeks on, one week off) with camp accommodation, flights and site allowances
- •Mining employers mostly pay under enterprise agreements or above award salary contracts that sit well above award rates
- •Big companies run their own apprentice intakes: Rio Tinto, for example, trains heavy duty diesel fitter apprentices through the Certificate III in Mobile Plant Technology with FIFO options
- •Strict site inductions, permits and isolation (lock out tag out) procedures rule everything you do
Agriculture and machinery dealers
Ag machinery dealers (John Deere, Case IH, New Holland and others), local workshops in country towns, and on farm field service. You work on tractors, headers, sprayers and seeding gear, plus whatever else rolls in.
- •Huge variety: engines, hydraulics, electrics, GPS guidance and precision ag tech on the same machine
- •Seasonal pressure around seeding and harvest, when long days and weekend work are normal because the crop will not wait
- •Plenty of field service in a ute or service truck, fixing machines in the paddock
- •Strong demand in regional areas, so it is a solid path if you want to stay in the country
- •Dealers often send you to factory training on top of TAFE, which is worth a lot on your resume
A day in the life (first year)
- ▹Start with a toolbox talk or prestart meeting, check the job board and grab your first service or repair job
- ▹Morning might be a full service on a prime mover: oils, filters, greasing, brake adjustments and a good look over everything for defects
- ▹After smoko you could be chasing a fault: plug in the scan tool, read fault codes, test sensors and wiring, then prove the fix
- ▹Heavier jobs run across days: pulling a gearbox or diff, stripping a wet end, or helping a tradesperson swap an engine
- ▹Field service days mean loading the service truck and driving out to a broken down truck, tractor or digger
- ▹Finish by writing up the job card, ordering parts for tomorrow and cleaning your bay, because a tidy workshop is a safe one
First-year expectations
- →Expect the basic jobs first: services, greasing, tyre rotations, washing parts and cleaning up. It is not glamorous but it is how you learn the machines
- →You will be the gofer for a while: fetching tools and parts, holding things, degreasing components. Watch closely while you do it, that is the real training
- →The gear is heavy and the days are physical. You finish filthy, and in summer a workshop or a mine site is hot work
- →TAFE blocks or day release run alongside work. Keep up with the theory because the electrical and diagnosis units catch people out
- →Your pay is apprentice pay, set by your award or agreement, your year and your age. It is lean early on, so budget properly
- →Show up on time, ask questions and look after your tools. First years who are keen and reliable get given better work fast
Tools you'll need
Common terms
- Diesel fitter
- Common name (especially in mining) for a mechanic who works on heavy diesel powered plant and equipment. Same trade family, different badge.
- Mobile plant
- Self propelled machinery like excavators, dozers, loaders and haul trucks, as opposed to trucks that run on the road.
- PM service
- Planned or preventive maintenance service done at set hours or kilometres to stop breakdowns before they happen.
- Air brakes
- Brake system on heavy vehicles that uses compressed air instead of hydraulic fluid. Air tanks, valves, boosters and slack adjusters.
- Driveline
- Everything that carries power from the engine to the wheels: clutch, gearbox, tailshaft, diff and final drives.
- Hydraulics
- Systems that use pressurised oil to do work: tipper hoists, excavator arms, steering and more. High pressure and unforgiving.
- Stored energy
- Energy still in a system after shutdown: compressed air, pressurised oil, raised loads, springs. It can kill you if it is not released or isolated first.
- Lock out tag out (LOTO)
- Isolation procedure where you lock a machine's energy sources off and tag them so nobody can start it while you are working on it.
- Scan tool
- Diagnostic computer you plug into a vehicle or machine to read fault codes and live data from the electronic control units.
- Field service
- Doing repairs out where the machine is (roadside, paddock or pit) from a service truck instead of in the workshop.
TAFE & study support
The off the job training is the Certificate III in Heavy Commercial Vehicle Mechanical Technology (or Mobile Plant Technology for the plant stream), delivered by TAFE or a private RTO in block release or day release while you work. The qualification is 36 units covering engines, brakes, driveline, hydraulics, electrical and diagnosis. Some employers, especially OEM dealers and mining companies, add their own factory or site training on top. Your training contract and state training authority set out how the TAFE side runs in your state.
Licensing & qualifications
The trade qualification is the AUR31120 Certificate III in Heavy Commercial Vehicle Mechanical Technology (current on training.gov.au), with the AUR31220 Certificate III in Mobile Plant Technology as the heavy plant equivalent. Diesel mechanics are not a licensed trade like electricians or plumbers, so there is no trade licence to hold before you can work. That said, tickets add a lot: forklift and elevating work platform (EWP) high risk work licences, air conditioning handling, and MR or HR truck licences so you can road test and move the vehicles you work on. In mining, site inductions and standard tickets are part of the deal.
What you'll get paid
Apprentice pay is not one national number: it depends on the award or enterprise agreement that covers your workshop, what year of the apprenticeship you are in, your age (adult apprentices who start at 21 or older get higher rates) and whether you finished year 12. Mining employers usually pay under enterprise agreements that sit well above award minimums, which is a big part of why the plant stream is popular. Check your own numbers with the Fair Work Pay and Conditions Tool at calculate.fairwork.gov.au.
Common questions
What is the difference between a diesel mechanic and a diesel fitter?
Mostly the world they work in. Diesel mechanic or heavy vehicle mechanic usually means trucks and buses (the AUR31120 qualification). Diesel fitter or plant mechanic usually means mining and earthmoving gear (often the AUR31220 Mobile Plant qualification). The skills overlap heavily and people move between the two.
How long does the apprenticeship take?
Nominally four years. Most awards allow competency based progression, so if you knock over the training requirements faster you can move up pay levels and potentially finish early. Adult apprentices with existing experience can sometimes get credit that shortens it.
Can I get into mining straight away as an apprentice?
Yes, the big miners and their contractors run apprentice intakes, some FIFO from capital cities and regional hubs. They are competitive: a pre apprenticeship, decent school results and a clean attitude help. Plenty of people also do their time in a transport or dealer workshop first, then move to mining once qualified, and the money jump comes then.
Is it a good trade if I did not love school?
You do not need to be academic, but do not believe anyone who says there is no theory. Modern trucks and plant are rolling computers, so the electrical and diagnostic units take real effort. If you like solving problems with your hands and you can push through the bookwork, you will be fine.
Do I need my truck licence?
Not to start. Once you are in the trade an MR or HR licence is very handy because you can road test trucks and drive the service truck, and many employers will help you get it. In the meantime a car licence matters, especially for field service and regional jobs.
GTO or direct employer, which is better?
Direct means the workshop employs you for the whole apprenticeship, which usually means deeper roots in one team. A group training organisation (GTO) employs you and places you with host workshops, handles your pay and paperwork, and can move you if a host goes quiet. GTOs are a solid backup if you cannot land a direct spot, and some rotate you through different types of work, which is good experience.
Safety reminders
- ⚠Never work under a truck or machine on a jack alone: it goes on stands or props rated for the weight, every time. People die under vehicles that were only held by hydraulics
- ⚠Respect stored energy: air tanks, brake spring chambers, hydraulic accumulators, raised bodies and buckets. Isolate, lock out, release pressure and fit safety props before you put hands in
- ⚠Split rim and large tyre work is specialist and dangerous: exploding rims and tyres are a known killer in heavy vehicle workshops, so follow the cage and inflation procedures exactly
- ⚠Hot work and fuel do not mix: diesel, hydraulic oil and batteries all burn or explode with the right ignition source, so control sparks, flames and fuel vapours
- ⚠Watch pinch and crush points around suspension, fifth wheels, tailgates and articulated machines, and never trust an unchocked wheel
- ⚠Look after your body and your ears: use lifting gear for heavy components, wear hearing protection around running diesels, and avoid skin contact with fuels, oils and injected hydraulic fluid (a pinhole hydraulic injection injury is a hospital job, always)
Sources and official links
Straight from the source. These open in a new tab.
- training.gov.au: AUR31120 Certificate III in Heavy Commercial Vehicle Mechanical Technology (opens in a new tab)
- training.gov.au: AUR31220 Certificate III in Mobile Plant Technology (opens in a new tab)
- Your Career: Diesel Motor Mechanic occupation profile (opens in a new tab)
- Jobs and Skills Australia: Diesel Motor Mechanics (ANZSCO 321212) (opens in a new tab)
- Fair Work Ombudsman: Apprentice and trainee pay rates (opens in a new tab)
- Fair Work Pay and Conditions Tool (opens in a new tab)
- NSW Education: Heavy Commercial Vehicle Mechanical Technology school based apprenticeship (opens in a new tab)
- Rio Tinto Future Skills: Apprentice heavy duty diesel fitter (opens in a new tab)
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