WordNet records no synonym and no antonym for wheeled vehicle. It is the only member of its synset, which is common for technical, taxonomic and single-sense vocabulary — there is no other English word that means the same thing. The broader and narrower terms below are the useful relations in that case.
Counts are distinct word forms across every sense. A synonym that appears under three senses is counted once here and shown three times below, under each sense it belongs to.
a vehicle that moves on wheels and usually has a container for transporting things or people
“the oldest known wheeled vehicles were found in Sumer and Syria and date from around 3500 BC”
Synonyms, antonyms and the broader and narrower relations for wheeled vehicle come from Princeton University’s WordNet. Full sources and licences.