Clicking noise when shifting into reverse + play in RF wheel

[Infinitiguy19]

For some time now every time I shift it Reverse and sometimes Drive I get a clicking noise from the back of the car. What could be causing this?

Also when I checked for a bad ball joint on the RF wheel I found there was play in the wheel. It is not the ball joint (not checked with a dial gauge). The whole upper link and king pin shake when shaking the wheel. But when I put a pry bar to pry up on the ball joint there is no movement. What could be the issue here?

[elwesso]

Clicking sound could be as simple as the brake pads moving in the calipers or the calipers moving on the pins.

As far as the play it kinda sounds like it could be in the upper link or kingpin. Can you tell where it's "pivoting"?