The bucket on my L3400 keeps slipping off. I checked the pins that hold it in place, and they were loose. Even when I tighten them completely, they don't seem to stay in place. I tried adjusting the springs, but it did not help. I compared my tractor to another, and it appears that the pins should be tightened. I tried several attachments, but they all had the same problem. I disassembled the pins to check for wear, but they appear to be in good condition.