The 29-year-old was arrested at junction 36 yesterday afternoon (December 29) after police received reports of a man stopping drivers and trying to sell them jewellery in exchange for money to buy fuel.
Cumbria Police said it had received a number of similar reports from drivers across the county in recent days.
Following his arrest, a spokesman for the force said: "Officers have arrested a man on suspicion of a fraud offence. The man is 29-years-old and from the Preston area.
"He was arrested after police were called yesterday afternoon (December 29) regarding a man said to be flagging down motorists at various roadside locations in the county and attempting to acquire money “for fuel” in exchange for jewellery.
"He was located at junction 36 of the M6 and arrested. He remains in police custody today."
Cumbria Police said it wants to speak to anyone who might have been approached by the man.
A spokesman added: "Officers would like to hear from anyone who suspects they may have been approached by the man.
"You can report online at cumbria.police.uk/reportit, quoting incident number 125 of 29 December 2021. You can also phone on 101."
Alternatively, you can contact Crimestoppers, anonymously, on 0800 555 111.