Colin Barrell, 55, an undertaker from Portsmouth, Hampshire, was taking part in a classic car expedition to Moscow delivering toys and clothes to the children of Chernobyl when the gearbox of the pounds 16,000 car broke.
After a rejection of help by the AA's European service headquarters, Mr Barrell contacted the AA's Basingstoke office. Staff there decided it was a challenge and began exploring ways of getting the car back.
'Local garages in Moscow hadn't got a clue about the workings of a Cadillac and neither had I. The American and Canadian embassies couldn't help either,' he said.
'I'd joined the AA Five Star European service just 14 days earlier, but when I rang their headquarters in France they said they couldn't help because I was outside Europe.
'On the off-chance, I phoned the AA in Basingstoke and someone there said they saw it as a challenge and would give it a go.'
The car was towed on low-loader lorries and eight days later was delivered to Mr Barrell's home.
An AA spokesman said: 'It was certainly the most ambitious rescue we have ever undertaken.
'The Cadillac was eventually deposited at his front door in Portsmouth and he is making arrangements for it to be repaired.'