hi there can any one help at work we have a stockman 284 tractor and the hydraulics have stoped working, when you use the leaver there is no noise of the pump trying to make them work, it was low on oil so we topped it up and worked slowly for awile. we have a topper on it at the mo and when the oil was hot it lifted the topper up but wouldnt let it down untill we drained all the oil out. we have put fresh oil in, 10w/40 transmission oil, does any one no if this is the right oil, we have no book on the tractor. have taken the leaver spool block apart and found nothing wrong. Has anyone any idea on what could be up with the tractor.