How we know

Sources

Declared fuel consumption and technical data. The EU heavy-duty vehicle CO₂ monitoring data, published by the European Environment Agency. For each new heavy lorry in scope, the manufacturer simulates the vehicle as built with the EU's VECTO tool on standard missions and payloads, and declares the result (Regulations (EU) 2017/2400 and 2018/956).

Registered figures. The Netherlands vehicle register (RDW Open Data) and the Finnish vehicle register (Traficom open data): one record per registered vehicle, with its dimensions and masses as registered.

Definitions. The EU regulations that define vehicle groups, missions and bodywork codes, quoted from the legislation itself.

What a page is

A page groups the vehicles our sources describe as one model: the name the manufacturer declares where it declares one, otherwise the range, declared engine power, axle configuration and chassis. A page is split when its records state two engines, two vehicle forms, two axle configurations or two type-approval generations. A model publishes only when it has the full core set — wheelbase, length, gross and kerb weight, engine power, vehicle form and axle configuration. Anything less has no page at all.

Why some figures are ranges

One page covers many vehicles built to different specifications. Where a figure differs between them — a wheelbase, a weight — there is no single true value, so we show the range, the median and what stands behind it: the declared configurations, or the type-approval versions where the rules fix that figure per version. Dimensions and kerb weights are not fixed by a type-approval version, so for those we can only count registrations.

How fuel is compared

A declared figure comes from the manufacturer's own submission under EU heavy-duty CO₂ monitoring: each vehicle as built, simulated with the EU's VECTO tool on a standard route at a stated payload.

A declared fuel figure is compared only with others on the same mission, payload, axle configuration, vehicle group, fuel and reporting year. A model is ranked when at least ten declared vehicles stand behind its figure, and a ranking needs five models from two makes. A gap under 10% is inside the tolerance of declared figures and is never presented as a reason to choose.

Figures the regulation does not define

The EU's heavy-lorry CO₂ rules, Regulation (EU) 2017/2400, list the inputs a manufacturer declares, but four of the figures we show from those declarations are listed with a unit and no description: gross vehicle mass (parameter P041) and chassis mass (P038) in Annex III, whether the cab is a sleeper cab (P276) in Annex III, and engine rated power (P250) in Annex V. We show them under the name the declaration uses and do not treat them as the same quantity as a register's technically permissible maximum mass, kerb weight or net engine power. Each carries a note saying so.

When sources disagree

If two sources give values for the same thing that cannot both be true, we show neither and say so. We never pick a winner. Claimed and measured figures differing is expected, not a disagreement; each is labelled.

We also check that one register does not give different values to vehicles of the same type-approval version. That check can only run where the register records the vehicle's type-approval number; where it does not, the figure is shown as a range over registrations and has not been checked version by version.

The drawings

Each model's side view is generated from its own recorded wheelbase, length and axle configuration. Parts no source records, such as the cab, are drawn to a stated convention and never dimensioned. It is a generic outline, never the manufacturer's design, and never a generated image of a real vehicle.

Spotted an error?

Tell us, with your source. We check it against ours and reply.