I think I saw it on Sky in the early 00s but can't be sure what channel. It was a smallish group of friends in their 20s from somewhere in the midlands UK, who all went on a crazy road trip across USA in a fully fitted out tour bus. There was lots of drinking and revelling and pairing up with people they met along the way, plus fall outs within the friendship group. They went from East Coast across to Las Vegas and ended up at the Burning Man festival I think. There was one couple and perhaps four other mates in the group.
To be honest none of them were particularly likeable! I don't why it has stuck in my mind - but I've been trying to remember what it was called to see if it was really as weird as I remembered it.