The VTG Plate Doesn't Tell You the Whole Story on Drive Axle Weight
On a recent audit, I came across an operator who was confident their weighbridge process was airtight. Drive axle showing 11,500 kg on the VTG plate, ticket coming in under that figure, box ticked. It's a reasonable position to hold, because 11,500 kg genuinely is the correct number. It's just not the only number that applies.
The legal position
11,500 kg is the manufacturer's design limit for the drive axle, set out in Schedule 3 of the Road Vehicles (Authorised Weight) Regulations 1998 (SI 1998/3111). It's the axle's maximum structural capacity, considered on its own, and it's exactly what the plate is supposed to show.
What the plate doesn't show is that a separate part of the same regulations, Schedule 2, governs the weight of the vehicle combination as a whole. To qualify for the higher weight bands available to 6-axle combinations, additional conditions apply on top of the Schedule 3 figures: conditions that never appear on the axle plate.
The relevant condition, confirmed in the text of the regulations:
> "the axle weight of each driving axle does not exceed 10,500 kg"
This was inserted by The Road Vehicles (Authorised Weight) (Amendment) Regulations 2000 (SI 2000/3224), effective 1 February 2001, when the 44-tonne, 6-axle tier was introduced, carrying forward a condition that already applied at the lower 41-tonne tier. It hasn't moved since, including through The Road Vehicles (Authorised Weight) (Amendment) Regulations 2023 (SI 2023/760), which increased weight allowances for alternatively fuelled and zero-emission vehicles but left individual axle limits unchanged.
The two figures, side by side
- 11,500 kg (Schedule 3): the manufacturer's design limit for the axle, in isolation
- 10,500 kg (Schedule 2, Table 3 condition): the same axle, once it's part of a 44-tonne, 6-axle combination
Both figures are correct. They answer different questions. A drive axle loaded above 10,500 kg on a 44-tonne combination fails the Schedule 2 conditions attaching to that weight band, regardless of what the plate says.
What could this actually cost?
DVSA uses a graduated fixed penalty scale for excess weight offences:
- Under 10% overweight: £100
- 10% to 14.99% overweight: £200
- 15% to 29.99% overweight: £300
- 30%+ overweight (or 5 tonnes+ excess): court summons, unlimited fine possible
Examiners generally allow a 5% leeway before issuing a penalty at all, except where the excess is 1 tonne or more, in which case that leeway doesn't apply.
Take a drive axle running 1 tonne over: 1,000 kg against the 10,500 kg legal limit is a 9.52% overload, into fixed penalty territory, at the £100 band. That's the immediate cost. The bigger exposure is what sits behind it: an axle overload and a combination weight breach are treated as separate offences, each with its own liability for both driver and operator, and a pattern of findings like this at a DVSA check is exactly the kind of thing that ends up in front of a Traffic Commissioner.
Why it's easy to miss
Nothing on the VTG plate cross-references the Schedule 2 condition. It's a separate provision, in a separate schedule, that only applies depending on which weight band the combination is actually running at. There's no natural point in a routine weighbridge check where the lower figure gets flagged unless someone is specifically looking for it, which is exactly how an experienced, careful operator can still end up working off the wrong number in good faith.
What to check
- Confirm which weight band your combination is actually operating in (41-tonne vs. 44-tonne conditions differ).
- Build the 10,500 kg drive-axle figure into weighbridge procedures directly, rather than relying on the plate alone.
- Treat the plate figure as the manufacturer's design limit, not automatically the applicable legal limit for every combination it might run in.
Sources: The Road Vehicles (Authorised Weight) Regulations 1998 (SI 1998/3111), Schedules 2 & 3: legislation.gov.uk/uksi/1998/3111/schedules/made · The Road Vehicles (Authorised Weight) (Amendment) Regulations 2000 (SI 2000/3224): legislation.gov.uk/uksi/2000/3224/made · The Road Vehicles (Authorised Weight) (Amendment) Regulations 2023 (SI 2023/760): legislation.gov.uk/uksi/2023/760/made
If your SOPs reference plate figures without the combination-level conditions, it's worth reviewing before a roadside check does it for you. Get in touch for an operational review.