The results from your testing indicate that to duplicate an original looking finish, the Por15/Behr finish looks and holds up the best.
Since Mar-K is probably the foremost authority on truck beds I’m sure that the question or original finish has come up and been thoroughly researched. After all, someone at GM had to specify the material and finish process and someone had to order the material and someone had to supply it and apply it. so there has to be some record of what was used.
The question that I have been asking for a couple of years here and with the VCCA is, what were the original materials and method of manufacture that GM used on the bed wood? They used wood in all their truck beds large and small for more than half a century so I'm sure that they had the finishing process pretty much down pat. The original bed wood (Southern Yellow Pine) in my 1950, 3604 is still solid even though the surface grain is raised and cracked on all of the boards. Some of the black is still showing in the surface of the wood and strips even after 58 years.
I don't believe that pressure treatment was in use back in the 40’s and 50's and I've heard that the boards were treated with or soaked with creosote, as were telephone poles and fence posts. Were the boards and strips both painted with black enamel paint? Were they painted before or after they were assembled in the bed? And finally, was the enamel that GM used on the bed floor a gloss or semi-gloss enamel?
Denny Graham
Sandwich, IL
