(WXYZ) - The FBI has done numerous searches for Hoffa's remains over the years.
Some question the wisdom of spending tax dollars on such an old case, others are skeptical of the information that prompted today's dig.
Nearly everyone is curious about what happened to Hoffa. It's one of America's greatest crime mysteries.
But there are some who say, enough already.
The tip that sparked this latest dig in Oakland County comes from Anthony Zerilli, the 85-year-old son of a reputed former mob boss.
Zerilli was in prison when Hoffa disappeared in 1975.
But some who have followed the Hoffa saga closely say Zerilli still could have good information.
"Even though he was in prison at the time Hoffa went missing he would have been in a position to have been told what happened. And that's his story," says the retired Special Agent for the FBI in Detroit.
The feds have chased down so many dead-end leads before, most recently when they tore up this driveway in Roseville looking for Hoffa's remains last September. They found nothing but dirt.
Some question why the feds are spending so much money on a 37-year-old case where the people involved in the disappearance are very likely dead.
"I wonder about, you know, about this money being spent. There's so many other things we could spend our money on. But, good story," said one bystander at the dig site who asked not to be identified.
Keith Corbett, a former federal prosecutor who ran the Organized Crime Strike Force says the FBI has an obligation to follow up on credible leads.
"You don't do a cost benefit analysis of criminal investigations, we tried to find out what happened. You know the FBI agents are going to get paid whether they're here or somewhere else," Corbett said.
But how credible is this latest tip? Zerilli has written a manuscript about his inside Hoffa information. While FBI agents were breaking ground looking for Hoffa's remains, Zerilli's attorney was meeting with reporters at the dig site and promoting a website where you can buy the manuscript and autographed photos of Zerilli. The attorney insists this is not about Zirelli cashing in.
"The FBI wouldn't have gotten a full warrant and affidavit and gone this far if it was just minute details. There's specific information that lead them to believe that the body is, the remains are there," said attorney David Chasnick.
Sources told 7 Action News that the FBI has been using heavy equipment, high tech equipment and good old-fashioned shovels for Oakland County dig.
The area they initially focused on was about ten feet by twenty feet but it could be expanded.