rear end problem
 

my 99 f150 4x4 rear end popping when i turn changed broken spider gears but it is still doing it help!!!

Check all the suspension components, body mounts and u-joints. It's a bit odd to feel/hear a popping noise in the rear while turning. How does the front end components looks and feel?

Is it coming from inside the differential housing?

Only thing is take cover off see what is going on.