When I turn the wheel all the way to the left, like when I'm parking, it feels like either the driver side front wheel is going over a bump, or that wheel shifts to the right and then back again.

Any body have ideas as to what this could be?

 

worn parts, look at the linkage and all the related parts as someone turns the wheel from lock to lock. or try to move the tie rod ends and ***** joints and look for up ward movement ,look for waron bushings.

 

I'm thinking that it could be the tire tubbing on the frame. As the car moves forward or back, the frame can be lifted by the tire. I would look at where the wheel is closest to the frame at full lock, and see if any paint/undrcoating is rubbed off. No real damage is done by this unless the tire getss cut up, and if you are worried about rust there is always a can of undercoating at the local parts store.