Ok, my truck has started having an issue occasionally over the last couple days. The steering feels like it wants to bind a little bit when the wheel gets to about the 3 o'clock position. When it does it you can feel a vibration in the steering wheel and it makes it sound like the engine changes pitch. It scares the crap out of you when it does it, but doesn't do it all the time. I have looked all over what i can see and can't find anything missing, broke, or rubbing. Is this the box or pump or? Any ideas would be helpful.