To make it more interesting, I had a '51 1.5 ton with a 1954 235 in it, and it had the oil filter option.
I took the oil pan off and there was at least a quarter pound of sand sludge in the bottom of the pan.
I think that the engine flush idea might eventually eat through the oil line blockage, but would like to hear from someone who has done a full purge. I'm not sure whether the sludge would stay in the bottom of the pan or clog the pump inlet.
