The MythBusters tried to pull the two phone books apart with human power, which was unsuccessful. A pair of cars also failed at pulling the phone books apart. Finally, the MythBusters resorted to using an M551 Sheridan light tank and an M113 armored personnel carrier, which were able to pull the phone books apart. While the myth was busted, the MythBusters pointed out that it took 8,000 pounds of force to pull the phone books apart, meaning that you could literally hang two full size cars from it.