Well here goes nothing. I am stumped. The shop said the banging when turning was the rear diff--"pieces of pinion gear" in the housing. So I opened up the differential (took back cover off) and the ring and pinion gears are perfect. Spun the wheels and watched with a flashlight. I then used a padded wrench as a lever to check for play or backlash--zero movement as if there is no space between ring and pinion. Turns freely but no play. I did this in park, neutral, and drive (engine off). So I then removed the "shackles" or rear half of bearing holders expecting to remove the innards. Nothing budges. The numerous youtubes I watched, the whole unit just tumbled out upon removing those shackles. I put a lever in there with not a hint of play---let alone coming out. 1). How could there be pieces of gears when there is no hint of even scuff marks? I cannot visualize the spider gears but if they are broken how did the pieces end up on the floor of the carrier (housing)? I would like to see them, the c-clips etc. but cannot budge the unit. Obviously I am missing something fundamental. I've never taken apart a diff. It's an 04 Titan with locker.