Denny,
Thanks for the info. It looks like one more mystery on my truck is solved.
It would be interesting to see just how much weight would have to be loaded to make the overload spring ends touch the auxiliary spring brackets, but I think I'll let someone else do the testing. As I said in the original post, I know 1800 lbs. won't do it although I realize that is only 300 lbs. of overload.
