It happened to me once too when I just got my previous car from service at Lamborghini dealer near DC (not FMoW). I drove for less than 50 miles and I feel the vibration at the back. The bolts are loose so I had to tighten them at the side of the road. It was the pain. From my experience, even the exotic car dealer that charge you arm and leg could screw up too. For us, not average drivers, should able to detect that kind of vibration and stop to take a look. But for normal or ignorant drivers, the result can be deadly. For me, I usually do not check the torque when get my car from service but I always aware of the vibration that is not normal.