When I turn on the headlands the steering cylinders jerk or do not operate smooth.  Noticed it today when ripping, plenty of oil, and brand new filters.   It holds the road great, small subtle turns are ok.  7000 hours on it, could it be steering valve issues or the metering pump that supplies the oil to the cylinders?   Hyd on the rest of tractor work great, and its both left and right turns.  Any advice would be appreciated, could continue using it the way it is but like things to work the way they should.   Might call mother deere tomorrow for a pressure test.