The engine shield fell down and would drag against the ground constantly, making awful grinding noises. When the roads were salted, the shield would scoop up all the salt and then fling it up underneath the car, causing a ton of noise as the salt particles flew around everywhere and fell back out. I never hit any debris or bottomed out in a way which might have caused this, so I am not sure why it happened, but I had to pay out of pocket because warranty did not cover this.