I have seen the joints go bad with very low mileage and low abuse levels. Makes a growling noise that transmits into the front end as well. If there is play in huge joint in a twisting motion, it is definitely bad. Before you throw more parts at it, check driveshaft joints, axle joints, and pull the diff cover off and check for broken teeth, especially on the pinion gear. Hard to see in there, but worth a look as checking things only costs you time and not $$$. A trick to see the pinion is to use your phone or a gopro and take a video while slowly turning the driveshaft. Then you can watch it and look for issues on your screen instead of trying to jam your head inside the diff.