Squealing

I AM NOT A CB TECH...I'll just chime in with my personal experience until the real brains answer. Where is your external speaker mounted? Factory tends to put them near your head somewhere...when you pull the mic to you, it tends to squeal in certain set ups. Back off your Mic Gain a little at a time and you may see the squeal go away. Full power? You must have a 10 meter maybe? I believe with a proper peak and tune and alignment, at least on my particular radio, I run the power turned all the way down. Of course there will be a hundred differing opinions about each and every detail.

If you have aftermarket external speaker, mount it away from you a bit and see if that don't help the squeal. That and mic gain...

 

What kind of radio? Back off the mic gain and see if that will help.

 

sounds like you have RF feedback many cars/trucks are fiberglass and this can be a problem.

 

Need to know what radio you have first of all. Also need to know if it has talkback and if you have the talk back on.

I am running an 04 379 pete also and every radio I have will squeal over the am/fm/CD player unless I have the wattage backed down to less then 4 watts.

Also your truck is equiped with a multiplexor setup which means the am/fm and your CB run through a box then out through the CB antennas. These multiplexor boxes are known to fail and cause some issues. you can try stopping into a truck stop and picking up a seperate single coax and unhooking one of the antennas and hooking the single coax to it then run it to your radio.

 

The Cascadias are notorious for this; I had to perform the fix you described in my truck. As for the OP, I'm tempted to think this is definitely a grounding issue, but not with his CB. If he pulls out his AM/FM stereo he might see that the chassis isn't grounded very well (if at all). if that's the case then installation of a simple grounding strap from the stereo chassis to vehicle ground may just do the trick.

I've also heard of people using ferrite beads around their stereo speaker wires. I suppose that could work, too; but it seems like an awful lot of work to me.

I also agree that, if you haven't already done so, back off a bit on the Dynamike (mic gain) setting. I also run a Cobra 29 LTD (mine has the Bluetooth function) with a 160W kicker, and having the mic gain at no more than 60% pretty much eliminated the feedback I was getting.