Reference: C15 s/n 2842129988 history and restoration

[Grant Bowker]

Old tire sidewalls have also been seen as isolators between transfer case and frame and are also one of the materials used at the forward can mounts for Cab 13. What was on any given truck for cab isolation seems to have depended on whether they were shorter of spring steel or rubber products at the time the truck was made. The service bulletins make reference to both types of cab isolator. A Cab 12 seen at Bob Carriere's field of dreams had strips of wood (oak?) along the top rail of the frame under the cab, too long to make out of single tire sidewall, even three pieces wouldn't be likely.