The commanders had a hydraulic accumulator that kept the hydraulic system pressurized after shut down. If you decide to work on the hydraulic system make sure you work the 3pt lever a few times to remove the built up pressure before cracking a line. Also be careful that the 3pt will move even with the tractor shut off. I know of two old time Ford mechanics and they both have said that the commanders required some additional respect when working around and on them.