Using oil issue
I'm with AJ on the oil pan overfill or fill as it was in my case. I had a 318 in my Duster once that I got out of a 1967 Satellite that would use oil like that if I tried to keep it at the full mark but if I let it stay a quart low it would stay at the add mark indefinitely. I couldn't figure it out because as far as I know it was the original dip stick but it didn't like having oil to the full mark.