I have been talking to  a trucking contracter today about the creamy oil in my road ranger gearbox and he asked if I have an air operated PTO . I have as it operates the hoist on my tipping tray. More than likelly that is where he thinks the water has got into the gearbox. I have to admit that I have been slack in draining the water out of the tank at times. Does the air operated valves need a service or just drain and flush the gearbox? Trucks are not my strong point, I am too busy growing wheat and merino sheep!