Just bought my first Commando

hi there. its possible the oil; seals have gone rock hard. to check you rear main seal is ok, remove the oil level plug on your primary transmission every now and again. If oild runs out, it can only come frome that oil seal provided the primary is not over filled in the first place. I just changed mine and the rubber seal had gone so hard, it broke when I squeezed it.
Dereck