Historically D&RGW MOW has been painted one of two colors, boxcar red (brown) or gray.
Until sometime in the 1940's, all MOW equipment was painted the boxcar red color. The change was made to gray during the Perlman regime.
I was told that the D&RGW bought a bunch of gray paint as war material surplus. I don't know the accuracy of that statement.
As a side bar: OY is actually historically incorrect painted boxcar red. As built it was painted boxcar red. However, by the time it received it's current tender (the former Unitah #30)it was painted gray.
Thanks, MAS