Doesn't sound necessarily like a hydraulic problem description to me. Hydraulically why would it bind in one direction and not the other, why would it hydraulically oscillate? Many people complain about these front ends, drift, looseness, steering oscillation. I am making an assumption, since you didn't write about it, that no one has tightened up the adjustment nut on the steering gear box. With a unit with 160K I would start at the wheels and work inward. Check for mechanical looseness / roughness in the wheel bearings, looseness in the ball joints and steering arm components. See what you find there. Probably get more hits on youre question to repost it in the 7.3 forum.