Heavy Vehicle Licensing and Licence Classes in Western Australia
How the classes stack
Western Australia licenses heavy vehicles by class, and each class is defined by the vehicle's gross vehicle mass (GVM), the trailer's gross trailer mass, and how the combination is configured. A car licence (class C) covers vehicles up to 4.5 tonnes GVM. A light rigid (LR) covers a rigid vehicle from 4.5 to 8 tonnes GVM, or a smaller vehicle towing a trailer up to 9 tonnes GTM. A medium rigid (MR) covers a rigid vehicle above 8 tonnes GVM with no more than two axles, plus a trailer up to 9 tonnes GTM. Heavy rigid (HR) covers any rigid vehicle above 8 tonnes GVM with three or more axles. Heavy combination (HC) covers a prime mover towing a semi-trailer, or a rigid vehicle towing a trailer heavier than 9 tonnes GTM. Multi-combination (MC) covers a prime mover towing two or more trailers.
The traps
Questions love the boundary cases. A two-axle truck at 8.5 tonnes is MR, not HR. A rigid truck with a dog trailer is HC only if the trailer exceeds 9 tonnes GTM; otherwise it may stay HR. Watch for 'GVM' versus 'tare' versus 'ATM' - only GVM and GTM drive the class. Another trap is the order of progression: you must hold the lower class before upgrading, and minimum time-in-class and age requirements apply. Learner and provisional conditions, logbook hours, and the requirement to carry the licence while driving are common distractors.
Rule of thumb
Count axles and read the mass plate. Rigid vehicle: two axles over 8 t = MR; three or more axles over 8 t = HR. Any trailer over 9 t GTM behind a rigid = HC. Two or more trailers = MC.
Worked example
A three-axle rigid tipper with GVM 16 t towing a trailer with GTM 6 t. The rigid is HR (over 8 t, three axles). The trailer is under 9 t GTM, so the class stays HR. If that trailer were 12 t GTM, the combination becomes HC.