My '04 Forester started to make rattles that appear to be exhaust related. It starts to rattle under the car when it is started up. When the car heats up the rattles diminish. Anything to worry about? Is it easy to fix?
It is pretty common for the heat shields around the exhaust to rattle, sometimes it is an easy fix and is nothing to worry about. Just the annoying factor of a rattle. I have seen rocks get between the shield and the exhaust and rattle and I have seen the shields just get loose over time and rattle, the only way to tell is to get under the car visually look for rocks and things and to tap on the shields with your had until you find the sorce of the rattle. From your description I am guessing your shields are rattleing because the metal expands as it gets hot and would make everything tighter. Hope this helps.