rear axle

Hey guys. Long time lurker, first time poster. I recently had my rear passenger axle replaced like hundreds of others. After that every time i go slowly over a bump or turn slowly i hear a little clunky rattle underneath. My dealership is truly a poor experience, so I'm reaching out here...

7/24/2020 - Purchased 2020 Jeep Gladiator Rubicon with upgraded Mud Tires I didn't even want. 7/26 - Hit the trail. Plowed it through the mud a bunch of times. It was covered in mud for sure and killed the alternator. Had it towed to the closest Jeep dealership. Russell Westbrook of Van Nuys...

I was putting Rubi shocks on my sport when I noticed a blue and yellow shock (Bilstein) between my frame and rear differential. I don’t recall seeing this at the dealership on the others. It does not have a part number and I can’t find mention of it anywhere on the web.