Happened to us in the mid 90's on the way to Wally World.
About 3 am on I95 near Savannah I hear a noise like a tire iron hitting the pavement. "oh oh, that can't be good". Exited immediately. Turned out pin sheared and I lost one leaf. Tires didn't jam up until I hit the brakes in the gas station parking lot. Had to jack it up and move the axle forward. Mechanic Tightened the shackles and on the way. Said I would make it to Orlando. Called Camping world. They wanted $$$$ to repair. Removed spring. Found a spring shop, and $20.00 later I was out the door with a repaired leaf assembly.
FYI. This was on a very under sprung Holiday rambler Aluma-lite. When we got home I had all the springs replaced/upgraded.