Has anyone experienced the irritating radio squeal in the upper bands of AM? Is there an easy fix for this, like a common ground issue? I'm fairly certain that its electrical interference but don't want to go digging around in the dash without knowing what to look for. Thanks.

 

Through the years there have been various chokes and supressors for this. It might be worthwile to look at ground connections, the antenna, the brushes and slip rings in alternator, and any suppressors that show up in wiring diagram.

 

I have the same problem and cant figure it out. If i turn on my parking lights or turn the truck off the interference goes away. If you figure it out post it.

 

you may be picking up electrical noise from the altenator which is louder with the higher voltage not sure but I think AM channels will pick it up easier not sure why, something I ve noticed for years when i used to install stereos