Hi! I have problems with the hydralic system on 8011 that will not work periodicly. Than all of a suden it starts to work. Not when the trackor i runing! It has to be left for some days or weekes. (resting?) This has happen about tre times over a period af 3-4 years. The problem has never been solved. Today the hydralic system is out of order! There is enough with oil in the gearbox and it has been changed recently. I have cleand the three filters on the left side of the gearbox. The switch for hydralic on/off is in the right position. After cleaning/emptying the topp filter refiting it, trying if the system works, I noticed that there was not speciely much oil in that filter when I took it apart an looked inside. Anyone how has a clue what to do next?