Load security, weight limits and load distribution
This section covers legal weight limits, axle loading and load restraint. The exam tests whether you can calculate a safe payload and recognise a load that is legal by volume but unsafe by weight or position.
Core rules
Every heavy vehicle has a gross vehicle weight (GVW), axle limits and sometimes a train weight. Payload is GVW minus kerb weight, fuel, driver and passengers. Distribute load so no axle is overloaded and the centre of gravity stays low and central. Secure loads with rated straps, chains or twist locks; check tension after the first few kilometres. Do not exceed height, width or rear overhang limits. A bulk load that looks small can still be overweight, and an uneven load can overload one axle while the total remains legal.
Worked example
A truck has a GVW of 18,000 kg and a kerb weight of 7,000 kg. Fuel, driver and passengers add 500 kg, leaving 10,500 kg payload. The customer loads 11,200 kg of bagged cement. The vehicle is 700 kg over GVW, so it must not leave the yard. The fix is to remove 700 kg, not to adjust tyre pressures.
Traps
Equating a full load bed with a legal load; ignoring axle limits because GVW is under; using unrated rope; and failing to recheck straps after the load settles.