(names and meaning of words have changed over the the thousand of years the stories are told on Nilfeheim. No one really remembers what a wagon or a chariot should look like. There are only very few things that use the wheel on Nilfeheim.)
Tanngrisnir (Old Norse "teeth-barer, snarler") and Tanngnjóstr (Old Norse "teeth grinder") are the goats who pull the god Thor's chariot in Norse mythology. They are attested in the Poetic Edda, compiled in the 13th century from earlier traditional sources, and the Prose Edda, written by Snorri Sturluson in the 13th century.
The Prose Edda relates that when Thor cooks the goats, their flesh provides sustenance for the god, and, after Thor resurrects them with his hammer, Mjöllnir, they are brought back to life the next day. According to the same source, Thor once stayed a night at the home of peasant farmers and shared with them his goat meal, yet one of their children, Þjálfi, broke one of the bones to suck out the marrow, resulting in the lameness of one of the goats upon resurrection. As a result, Thor maintains Þjálfi and his sister Röskva as his servants. Scholars have linked the ever-replenishing goats to Scandinavian folk beliefs involving herring bones and witchcraft.