Noise from steering when backing up
 

2008 Boxster, when backing up and turning with the steering wheel at full lock, there is a slight thumping, bumping noise which can also be felt in the steering wheel. Worse when turning left but happens on both sides. Can’t see anything rubbing. Steering feels tight with no play. Wheel bearings feel tight.
Any ideas?

If you move forward, at the same (slow) speed, with the steering at full lock, do you also experience the same thing?

There is no noise going forward at full lock in either direction.

Look at ball joints, tie rod ends, bushings.

I'm redoing the suspension and brakes on my 1998 and many of the rubber parts are bad.