Shiny threads or rust trails on lug nuts could indicate _________.

When lug nuts are loose, the lug nuts will rub against the wheel, causing the threads to become shiny or the rust to be worn off. This can be a serious safety hazard, as loose lug nuts can cause the wheel to come off while the vehicle is in motion. You should:
- Check that all lug nuts are present, free of cracks and distortions and show no signs of looseness such as rust trails or shiny threads.
- Make sure all bolt holes are not cracked or distorted.