You need to fit a different washer, An Anti Shake type or what I call a Star washer like the top left in the link below as it helps to keep the contact through the muck and grease
Andy C
I know this sounds rather rudimentary and simplistic but since it actually has fallen off I have to start from the beginning. Did you tighten the bolt holding the post? Could the bolt be stripped? Is the post eaten up or worn smaller than the clamp?
Your post may be worn to the point where tightening the clamp bottoms out and prevents a snug fit. If so, you can use a shim. I have done a temporary fix in the past by lightly tapping a small screw between the post and clamp. An emergency fix until you can get it to an auto parts store for a proper shim.
Replace the battery cable.
Go to auto parts store and get a new cable. Probably needs one by now anyway. Not very expensive.
Yes
They sell shims http://www.autozone.com/electrical/batte...
You need new battery cables.
I drive a 1995 Pontiac firebird and I recently disconnected my negative charge on my battery. I reconnected it and now I've been frequently having problems with it. Sometimes my car won't start and I have to get out to fiddle with the negative connection, sometimes it just disconnects when I'm driving and my car shuts down, and I've tried to reconnect it as tight as possible but it still doesn't solve my problem. The actually connection still stays in the terminal attached to the battery, but I have to constantly mess with the actual bolt until I can get my car to start. Any suggestions?