"You've got borrowers who are under water. This is just like the subprime loan crisis," said Keith Leggett, a credit union analyst and former senior economist at the American Bankers Association.
LOMTO Federal Credit Union, which was founded by taxi drivers in 1936 for mutual assistance, was placed into conservatorship by the National Credit Union Administration on June 26 "because of unsafe and unsound practices."
New York City has the nation's largest taxi industry, with more than 13,000 medallions.
Marcelino Hervias bought his medallion in 1990 for about $120,000 and thought its value would hit $2 million by the time he was ready to retire.
Instead, the 58-year-old said he owes $541,000 and is driving 12 to 16 hours a day to make ends meet.
"I celebrate my kids' birthdays over the phone. Why?" Hervias said.
While some medallions are held by large owners with fleets, owning a single medallion was long seen as a ticket to the middle class for immigrants like Hervias, who is from Peru.
Many of them now owe more on their medallion loans than they originally paid for the medallions because they used their equity in the medallion for a home, a child's education or other expenses.
Hervias said he borrowed against his medallion to pay for medical care for his mother, a new car and a visit to his homeland.
"Every time we want to go on vacation or do something, where do we go? To the equity of the medallion," he said.
Other medallion owners tell similar stories.
Constant Granvil bought his medallion for $102,000 in 1987 and said he now owes more than $300,000 to his lender. He could have sold the medallion for two or three times that a few years ago, "but I said no, I'm not going to sell it," said Granvil, who is 76. "And then I got caught."
The value of Granvil's medallion is hard to pinpoint because 2017 sale prices have varied from the $200,000s to the $500,000s depending on whether lenders are willing to finance the purchase.
Meanwhile, Granvil, who no longer drives because of poor health and uses a broker to hire a driver, said he is facing threats from the lender, Melrose Credit Union, to foreclose on not just his medallion, but also his house.
"How am I going to live?" he said. "And now Melrose wants to take my house?"