My '51 1-1/2 ton 6400 fire truck has the "Load Master" engine, the 235, which I think was pretty standard for 1.5 tons. Think mine might of been grey, when it wasn't grime-black.
Speaking of which, in cleaning a valve-cover from another truck, the "Hi Tork Load Master" script rubbed off the cover. Are there stencils or decals available for these?
-Michael