Alteredgasser57

Hey guys, so the other day, I dug out my associated rc18t rtr version 1. I've had this rig for a while (since I was five or six) and like all my trucks, its had a few upgrade. Upgrades include: 5800 kv brushless system, front cvd shafts (still rockin' the sprins and dog bones in the rear), associated 18mt tires, and a spektrum 2.4 radio setup. Now for the issue... Just recently I was ripping this thing around in a hotel parking lot on a 2s lipo, and after some good fun, the rear gears in the diff housing started making this awful clicking noise. After inspection, all the gears are intact, but I have no idea what is causing this new clicking sound, and how to fix it. I have had the rig apart, and still can't seem to diagnose the issue. Any help would be greatly appreciated. Thanks!