2016 CADILLAC ATS Suspension Problems

My 2016 Cadillac ATS Coupe has a serious repeating safety defect. The vehicle violently shakes, vibrates, and becomes unstable while driving. This happened TWICE. Both times the rear bolts came out except one. Both mechanics who inspected it said they have NEVER seen this before. The first time, I paid $4,000 out of pocket at another shop. The problem happened again, proving this is a manufacturing defect. My AXP diagnostic on November 4, 2025 confirms major rear differential/axle issues. The vehicle is unsafe and undrivable. One mechanic told me DO NOT DRIVE IT. Cadillac told me the opposite — “safe to pick up” — even though they did no real diagnostic. Cadillac refused to give anything in writing, refused a loaner, and ignored multiple emails. A Cadillac representative told me they reviewed the previous calls, meaning they know the full history. They still refused to fix the dangerous defect. I...