what do you call the bolts that hold the car body to the frame

Hi what are the long bolts called that hold the frame to the body of the car-one is located on the driver side and then one is located on the passenger side, and I am missing one-but I need to know what they are called so I can order one. They have a large washer on them with rubber bushing behind the bolt-my mechanic says its a long bolt and driving the car without all bolts attached would not be safe. He saw this when he put the car on the hoist, they are attached right on the front carriage-on opposite corners of the front carriage.