Dennis Clift, from Chelmsford, Essex, grabbed two-week-old Charlie O'Sullivan from the wreckage of a BMW on the M6 in Warwickshire in 1999.
Ever since he has received a Christmas card from the O'Sullivans and wants to return the gesture.
Searches with local authorities and on social media have come to nothing.
"I've tried everything, Facebook, Devon County Council, but I can't find them," he said.
Mr Clift, who was a breakdown recovery man at the time, was travelling back from Birmingham when he saw Jane O'Sullivan's car in flames on the hard shoulder of the motorway.
"Jane had been in the car with her two children and a baby was still on the back seat," he said.
"I went and rescued him.
"I've received a Christmas card every year since and I'd like to send a card back and they've asked me to come down, but I don't where they live."
Mr Clift parked his truck across the carriageway to stop the traffic until police and fire crews arrived.
Mrs O'Sullivan was treated in hospital for shock and minor burns. Mr Clift, Charlie and Mrs O'Sullivan's 14-week-old daughter Rosie were uninjured.

The John Muir Trust has carried out its latest clean-up of Ben Nevis after the thaw of winter snow.
Last September, trust volunteers found as many as 1,000 banana skins dropped at the summit.
Walkers and climbers were warned that the skins take up to two years to break down and did not biodegrade as quickly as they may think.
Plastic bottle and tissues have also been collected in the latest clean-up.
Sarah Lewis, trust conservation officer, said most walkers and climbers dealt with their litter responsibly.
She added: "But it is clear that some people just don't see the impact that their litter has - 100,000 people climb up Ben Nevis every year, so if even a tiny minority of them leave their litter it can quickly build up."

The Australian won three league titles as a Tigers coach, working under former director of rugby Richard Cockerill.
"I cut my teeth in the Premiership," O'Connor told BBC Radio Leicester ahead of Newcastle's visit to Welford Road.
"I've got a good understanding of what is required in this part of the world to win trophies."
O'Connor, 46, coached at Leicester between 2010 and 2013, before leaving to take the top job at Leinster and subsequently going to work for Queensland Reds and Tonga.
He has now returned to replace Aaron Mauger, who had succeeded Cockerill in January.
"It is fantastic to be back," O'Connor said.
"I've got nothing but fond memories of the years spent here previously and I'm really looking forward to starting that legacy up again, hopefully.
"To be a part of one of the most successful rugby clubs in the world again was a fantastic opportunity too good not to pursue."
O'Connor has been given his old job title of head coach, but this time will take full charge of team affairs, with the club changing the coaching structure in the absence of a director of rugby.
And he believes the players now need to take this as a fresh start as they fight Bath for a top-four spot.
He said: "I think given the story of the season and the different philosophies that have been significant in the group there is a bit of clarity that needs to be brought.
"If we adjust a few of the things that we are doing on both sides of the ball I think it is an exciting three games and everything to play for."
A truck driver who saved a baby from a motorway fireball is trying to find the boy's Devon family so he can send them a Christmas card.
[NEXT_CONCEPT]
Discarded banana skins are still being found on Britain's highest mountain despite warnings from conservationists.
[NEXT_CONCEPT]
Matt O'Connor believes he will fit back into the Premiership seamlessly as he prepares for his first home game in full charge of Leicester Tigers.