ball joint?

 

Would you only hear the ball joint pop while the truck is moving slowly though? I can leave it parked and crak the wheels all the way one way and all the way the other without making the popping sound and I can make right and left hand turns around the 15-20mph range without making the popping sound.

 

not sure. ive heard when a ball joint is going it can make a crackling or popping sound...