Jerry, a couple of things come to mind. How is your steering damper? A power steering box needs inputs to produce outputs. If you are saying that after a left turn and after you bring the wheel to center, it will start to track to the left. How are you making the determination? W/O any steering inputs from you, ie. corrective or neutral inputs, the car still tracks to the left and/or to the right. Are you driving on the highway? Is the road noticeably crowned? When you describe a turn to the left or right, is it a small steering displacement or a large one at low speed? If it wanders at speed, either to the right or left, then it can only be a steering component or something amiss in the suspension, usually the toe angle.. Another thought.. make sure the universal coupling between the steering shaft and the steering box is not loose or damaged. It is easy to miss something when inspecting a suspension. Control arm bushings can also be suspect. I guess it would help to know how severe the pull actually is..
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.