On my work van I got a leaf added for the extra weight I was carrying. When I did that the bushings started to squeak . Drives me nuts. I have to keep squirting oil on the bushings to keep them quiet. I wonder if your having a similar issue? I can't remember if you got new leaf springs of removed a leaf?
I dearched the leaf springs. Which seem to have an added leaf.
I also added new poly bushings in both ends of the leafs.
I don't think thats it though. The sound was more of a rubbing whizzing sound, like something rubbing as it turned.
Jason
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