I have a 300CI 92 F150 4x4, with the 5 speed tranny. I just recently replaced my steering box. Not too hard. However, I noticed another problem and have my suspicions, but I wanted to get other opinions. The truck also has a 4 inch lift with 33x12.5 tires.

Here's the problem: When I am moving slowly (usually in neutral when I am parking for instance) and turning the wheel lots, I seem to "run out" of power assist. This means I either blip the throttle to "regain" assist or friggin manhandle the steering. This seems to happen at some very inopportune times and I've almost had to change my shorts a few times because I'm not thinking about it.

Question is this:
1. I recently replaced the steering box that was leaking. As such, the power steering pump probably was driven at 1/2 full for a while. Could have this damaged the pump, since the resevoir was not full with power steering fluid all the time?

2. If I replace the PS pump, is there a HEAVY DUTY pump I can use? Should I use a different (than stock inline 6) pump? Perhaps one for a larger truck? Especially since I have larger tires?

I just hate running out of assist and want this problem to go away. Any help is appreciated. Thanks. Jim B.