My 07’ rockers have perforated and rusted through the bottom on both sides. My aunts 2008 Eddie Bauer has as well. The rust generally slows down after perforation because water no longer stays in the panel. Ford used cheap and thin steel for the rockers along with poor paint on the inside of the panel. This coupled with poor drain design is a recipe for disaster. Here in Western NY EVERY Expedition on the road from about 2010 back has rusted rocker panels. Failure on fords part....I have yet to see any 07-08 Tahoes with rusting rockers but every expy has the issue.
I purchased 06’ rocker panels from KeyStone and sprayed them but have been procrastinating the job. Generally the outer rocker panels rust on these and the inners stay decent.