Overweight Axle After Loading at a Grain Elevator
You arrive at a grain elevator with a three-axle Category C truck (two rear axles, one front) and a tandem-axle trailer, permitted maximum gross combination mass 40 t. The loader fills the trailer first and then the body. After loading, the elevator's platform scale shows: front axle 7.6 t, rear axle group 19.4 t, trailer axle group 15.8 t, gross 42.8 t. The plate on the front axle states a design axle load of 7.5 t. The route out crosses a bridge with a posted 40 t gross limit and a 10 t axle limit. You have a delivery window in 90 minutes and the alternative route is 40 km longer.
1. Which limits are actually breached, and what does that mean for moving the vehicle?
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Compare each figure to its limit, not just the gross:
- Gross 42.8 t against 40 t permitted and a 40 t bridge: breached by 2.8 t.
- Front axle 7.6 t against a 7.5 t design load: breached by 0.1 t, and front axle overload directly degrades steering and braking.
- Rear group 19.4 t and trailer group 15.8 t: need the plated group limits to judge, but combined they carry 35.2 t of the load, so the imbalance is the root cause.
Because the gross and an axle are over, the vehicle may not proceed onto a public road, and certainly not over the posted bridge. The correct action is to return to the loader and redistribute or remove load, then re-weigh. Driving to the customer and hoping not to be stopped is not a judgement call but a violation, and an overloaded combination on a 40 t bridge is a structural risk to others.
2. How should the load be redistributed, and what checks confirm the fix?
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The front axle is only 0.1 t over, while the trailer is carrying disproportionately. Shift load rearward within the trailer's legal envelope and forward off the trailer group toward the drive axles, keeping the centre of gravity low and ahead of the trailer's rear axle. Practical sequence: remove or shift about 3 t net to bring gross to 40 t or below, then re-weigh each axle group individually.
Confirm with three checks: (1) every axle and group at or under its plate value; (2) gross at or under 40 t and under the bridge posting; (3) the load is secured and the centre of gravity has not moved so far back that the front axle is unloaded below its minimum, which would lighten steering. If the re-weigh still shows an axle over, remove load rather than shuffle it, because shuffling only moves the excess.
3. It is now 15 minutes before the window closes. What do you tell the dispatcher?
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State facts, not preferences: the vehicle is over gross by 2.8 t and over on the front axle, so it is not road-legal and cannot use the posted bridge; re-weighing and adjustment will take roughly 30-45 minutes; the delivery will be late or must be re-slotted.
Do not accept a dispatcher's instruction to run anyway. Legal responsibility for the vehicle's condition rests with the driver, and pressure from a schedule is not a defence. Offer options: partial delivery of the legal load now with the balance on a second run, or a re-booked window. Record the scale tickets before and after adjustment, because they are your evidence if the load is later questioned.