Jeremy Clarkson even swears in his sleep, his Top Gear colleague James May has disclosed.
May told Jonathan Ross's chat show that sharing a tent with the straight-talking Yorkshireman was like being with "a giant swearing maggot".
The pair bunked up together during a bid to become the first people to drive a car to the Magnetic North Pole.
Top Gear was rapped by the BBC Trust last July for showing Clarkson and May sipping gin and tonics at the wheel during the stunt.
They used a heavily modified Toyota pick-up truck, while Richard Hammond raced against them in a sled pulled by dogs.
May told Ross the Top Gear team were doing their bit for the environment, saying: "We're hastening the demise of cars because we just treat them as a laughing stock."
* The episode of Friday Night with Jonathan Ross airs tonight at 10.35pm on BBC1.