i measured 2, my 66 *" and a 58/59 ford axle. I thne measure the axles so i could order some mosers and those were 30 3/8" and 26 1/8" which equals 56 1/2". then there is that gap inside the locker (axles dont touch), thats how i got 57 1/4" (estimate). but theres no way mine was less the 56...