I've had my 2000 LS since new and it has been perfect. Now I'm seeing rust only on the panel that is just behind the back door and in front of the rear tire.
it's in the area below the belt line. I'm getting some bubling in the middle of one side and some on the lower portion of the other side. Before I start to dig at it and try to fix I need to find out why this has happend. no rust anyplace else and the truck is in the northeast...
I would appreciate any insight

 

Welcome to the forum.

Since it's bubbling on the outside, that means the rust started on the backside and has eaten its way thru. Probably require a competent body man to replace some metal and repaint the area.