Wheel bearing freeplay
 

I jack my rear end up and put my hands on the top and bottom of the tire and rocked it. It had freeplay. My question is do I tighten the axle or replace the bearing

If you are sure it's the bearing moving and not the upper ball joint or a bushing somewhere moving then it's time to change the bearing. Damn burnouts will do that.

Damn the person who had it before me. Yea its the bearing. I hear it grinding at parking lot speeds.