The Top Gear presenter was joined by Lance Corporal Matt Croucher and Private Derek Derenalagi as he accepted the one millionth Range Rover produced in Britain on behalf of Help for Heroes.
Standing in between the pair at the event in Earls Court, west London, Clarkson joked: “Guess which one of us wasn’t ever a soldier.”
Lance Corporal Croucher, 26, of Solihull, Birmingham, was awarded the George Cross, the highest medal for gallantry not in the face of the enemy, after throwing himself on a grenade in Afghanistan in 2008, saving the lives of three comrades.
He escaped unscathed, except for minor injuries, when his rucksack took the force of the blast.
He said it was “fitting” that a car produced by Land Rover was being sold to raise money for Help for Heroes.
“Every single person that has been in the British military has used a Land Rover at some point in their career,” he said.
“It is the best four-by-four in the world by far, which is why the Ministry of Defence uses it.”
Private Derenalagi, 35, from Fiji, lost both his legs during a Taliban attack in Helmand in 2007 but is currently training in athletics in the hope of representing Britain in the 2012 Paralympics.
He said: “Help for Heroes funded a trip to San Diego as part of the Battle Back programme which helped me discover athletics for the first time.”
The £85,000 Vogue, which had the number plate “1,000,000”, will be sold at auction later this year to raise money for Help for Heroes.
The charity supports members of the Armed Forces who were wounded in action and Clarkson is one of its patrons.
Clarkson said: “Help for Heroes is just the most incredible success story.
“They do everything from building a swimming pool to completely changing the way wounded soldiers are viewed in this country and I’m very proud to support them.”
He said: “I was just doing some maths and I can’t believe it’s the millionth.
“I feel like we’ve got a bit of history here.”