When I worked for Goodyear. We had a single post lift fail. Co-worker was raising a car up. Was getting ready to go and set the safety. When a line failed under the concrete. Slamming the car to the ground. Figure the car fell about 7ft. I was off that day thank God. When they jack hammered the concrete. The line that failed was rusted through.
So they fixed that one. Then took the other 8 out of service one at a time and replaced all of the lines.
