I had an 06 Revolution…… Great coaches btw.... I believe if I recall only two of the reds were stop turn...…. I was always having an issue with corrosion where the bulb makes contact in the socket. I swapped out the long screws that held on the lenses with stainless steel ones. I also greased the screws because they were sometimes difficult to get out.
Check the bulbs and socket connections first. If you have SOME lights on the back working I doubt you have fuse or relay issues. I was always having someone tell me "you have a brake light out" Check bulbs and connections.
Glen and Nancy~ Media, Pa (Phila area)
2000 Fleetwood Discovery (G) / Cummins Diesel
'99 Jeep Wrangler