Never thought I'd be asking this question ... but?

I have a 06 and live in MI, right in the middle of salt central. I wash my truck often and I have 0 rust issues and at 99870k miles it is driven in the winter. replacement of rockers is still cheaper then a new truck. buddy at work replaced all 4 doors, the 8ft bed, both bumpers,rockers, and a paint job including entire under side with POR-15 on his 99SD diesel for 8k. most would say he is crazy but he loves his manual stick diesel and can not afford a new truck.