why does my 2001 ford explorer "drift" a few feet when parked on our slight inclined drive way?
A few feet? Normally it should roll a couple of inches at most before the "park pawl" inside the transmission catches. YOur problem probably lies there.
How do I fix?
You could also have a worn out U-Joint of the drive shaft which could also cause your problem. But I have never seen one while will allow the vehicle to roll a "few feet". The u-joint route is the easiest to check and you can replace one for about forty bucks. If it is the pawl, it is going to be beyond your ability to repair.
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