The Overweight Load on the Way to the Market
You drive a rigid six-wheeler with a tare mass of 9.2 t and a GVM of 24 t. You load 14 pallets of bagged fertiliser, each labelled 1.0 t. Before leaving the depot you note the steer axle reading is 6.4 t, and the combined drive-and-tag group reads 17.1 t. The steer axle limit on your compliance plate is 6.5 t, the group limit is 16.5 t, and the GVM is 24 t. The trip is 40 km on a suburban route with a fixed weighbridge 15 km ahead. The loader tells you the load is 'about right' and that other drivers run this load daily. Your schedule has a 30-minute buffer only.
1. Using the figures given, decide whether you can legally depart. Show your arithmetic.
Read the worked answer
Total mass = tare 9.2 t + load 14 × 1.0 t = 23.2 t, which is under the 24 t GVM, so GVM alone is satisfied.
Axle check:
- Steer: 6.4 t vs 6.5 t limit → 0.1 t (100 kg) margin. Legal but very tight; any load shift forward puts you over.
- Drive-and-tag group: 17.1 t vs 16.5 t limit → 0.6 t (600 kg) over. This is the decisive figure.
So despite the GVM being fine, the vehicle is not legal to depart because the axle group is overloaded. GVM compliance does not excuse an axle-group breach - the bridge at 15 km will detect the group mass, not just the total.
Note also the discrepancy: 14 t of declared load plus 9.2 t tare should give 23.2 t total, but 6.4 + 17.1 = 23.5 t. The 300 kg gap suggests the pallet labels understate actual mass. Treat the scale readings, not the labels, as authoritative.
2. What are your options before moving, and which do you choose?
Read the worked answer
Options:
- Redistribute the load - shift pallets rearward off the steer and drive axles toward the tag. But the steer is already at 6.4 t and the group is 0.6 t over; shifting rearward relieves the group only if mass moves behind the drive axles onto the tag, which is still inside the same group. The group total does not change by redistribution within the group. Redistribution only helps if mass can move to an axle outside the group (it cannot on a rigid) - so this will not fix a group overload.
- Remove load - take off at least 0.6 t plus a safety margin (say one pallet, 1.0 t) to bring the group to ~16.1 t. This is the reliable fix.
- Depart and 'sort it out' - not acceptable. Knowingly departing overloaded is a mass offence and the 15 km weighbridge makes detection near-certain.
Choose option 2: remove at least one pallet, re-weigh both the steer and the group, and only depart when every axle and group is under limit with a working margin. Recheck the steer after unloading, since removing rear mass can slightly change steer loading. Log the re-weigh figures.
3. The loader's comment that 'other drivers run this load daily' - how should that affect your decision?
Read the worked answer
It should not change it at all. Mass limits attach to your vehicle's compliance plate and the applicable axle/group limits on the route, not to a depot norm. A practice being common does not make it lawful, and if other drivers are running 17.1 t on a 16.5 t group they are each committing an offence. Your duty is to ensure the vehicle complies before it moves; 'everyone does it' is not a defence and does not transfer responsibility to the loader. Politely decline, fix the load, and if the loader insists, escalate to the operator rather than depart non-compliant.