I have an agervating rattle in my cab have done no mods other than speaker in rear and cargo box out. It only happens when no passenger is in truck. Its like a rubbing rattleing sqeaking sound. So I thought seat but I dont think so after lots of looking sounds like under dash? Need help going slowly insane from sound.

 

Check your slider window.

Mine rattles a little when cold.

If its when you're blasting the stereo, check your sunglasses console. I stuffed mine with napkins.

Daniel

 

This was at one time referred to as the "3 Man" rattle. If you have had your exhaust raised or even straight from the factory, it was possible to have the cab floor flex enough with a passenger on board to have the cab floor just touch the top of the muffler, causing the rattle.

There is a flange in the flooring just above the front of the muffler that is the issue. Try getting the muffler pulled away just a hair. Should solve it.

Your mileage may vary.