The classes the registers sort by

New commercial vehicles sit in seven classes: trucks, buses, pickups and small commercial vehicles, three-wheelers, tippers, tractor-trailer prime movers and special purpose vehicles. A vehicle sits in exactly one class, and search, comparison and the news wire all follow the same seven. Construction machines (excavators, loaders, cranes, forklifts and the rest) and farm machines (tractors, harvesters, rice transplanters, power tillers and certified farm drones) have registers of their own, each with its own classes.

Three-wheelers are a class of their own rather than a footnote under pickups, because a buyer choosing between a cargo three-wheeler and a small pickup is making a real decision and deserves both sides properly listed. Passenger cars are not on the register at all.

Within a class, body types are named the same way across every maker, so a tipper body is a tipper body whichever badge is on the grille. That is what makes filtering honest: a search for one thing returns that thing, not everything a maker happens to call by that word.