Thanks ear, the M and H are similar, the C and B and the A are similar and the Cub is like a miniature A as far as the Hydraulic units go. We had a couple M's when I was a kid, and an older C. The M's were sold over 20 years ago, the C still rakes hay every summer, we have also bought an H (about 10 years ago) that dad likes to rake hay with and do some of the lighter jobs around the farm...anyway thanks for the effort, I'll try cleaning the screens and flushing with Hytran, then filling with hytran. I don't know what is in there, I just bought it last year.