If your vehicle is showing rust spots bubbling under the paint, here are the most likely causes and the parts you'll need to fix each one.
Small rocks or road debris chip the clear coat and paint down to the bare metal. Moisture enters these tiny exposed areas and causes rust to form, which expands and bubbles the surrounding paint.
Salt, dirt, and moisture accumulate behind body panels like wheel wells, lower doors, or rocker panels. The metal rusts completely through from the inside, eventually pushing up and bubbling the outer paint.
If a previous repair was not prepped correctly, or if moisture/contaminants were trapped under the primer or body filler, rust will form underneath and bubble the new paint.
Failing weatherstripping or window moldings can trap water directly against the metal body. Over time, this constant moisture degrades the paint and causes rust bubbles around the edges of the glass or roof.