Watch: Jeremy Clarkson had a near-death experience with a caravan filming The Grand Tour
May, 58, told The Sun he thought Clarkson may have been killed when his car's tow bar broke whilst he was turning a tight corner as they travelled the Scottish Highlands.
May said: "For half a second I thought the whole rig had gone off the edge. I thought, 'We are finally shot of Jeremy, with his beloved caravan.'"
Clarkson added: "There was a point, when it started to overtake me, that I thought, 'God I’m having the biggest accident of my life'.
"Then I thought, 'No, wait, I’m still in control'. And then, 'The caravan’s come off', and the whole tow bar had detached.
"That really happened. I thought James’s lungs were going to come out, he was laughing so much."
The former Top Gear presenter insisted that for once the caravan accident had not been planned a stunt.
He said: “On that occasion, that was a pure, genuine, 100% accident.”
The The Grand Tour has become a hit TV series for the former Top Gear stars by featuring impressive supercars, daring stunts and exotic locations.
But due to the coronavirus pandemic and subsequent lockdowns and travel restrictions the latest series features the trio driving classic American cars around the winding streets of Edinburgh and the scenic coastline of the Highlands.
And as many hotels were closed they had to resort to staying in caravans for part of their journey.
Producer Andy Wilman told Yahoo: “This is smaller scale and once that happens, you dig deeper and the presenters inherently bring their own A-game.
"They ramp it up more because you’ve got nothing more to work with.
"And they had not been together for so long, that the banter was on the level of 10 years ago, there’s more of an innocence and a 'gang' thing to it.
Watch: Jeremy Clarkson on filming the latest series of The Grand Tour