Ran the Rubicon Trail for the first time over the past two days. Intermittently I would lose power steering. At first I thought maybe my front locker was failing to disengage, but it became clear that it was the steering. I had no leaks in the lines, and the fluid level remained constant (correct level). Any thoughts on the culprit? Steering box? Pump? Should I just upgrade/replace the whole system? It finally completely gave out on the way home from the trail (steering without power is no fun off the highway).