Loud ringing/squealing when the car is not accelerating

I have a 99 Explorer with 91000 miles on it. When i’m not accelerating or over 40 mph per hour, I hear a loud squealing sound when the car has been running for a while. My uncle/mechanic didn’t hear the sound when he looked at it and couldn’t find anything wrong with the car. The squealing has gotten progessively more frequent.

Belt squeal or a metal to metal squeal?

The squeal may be there, and your uncle may not hear it because the abilty to hear higher pitched sounds lessens as one becomes older. Let a younger mechanic listen for it.

Not sure…It started as a loud humming and now is more like ringing. Groaning even. It happens when the car is on for a while and sitting in traffic usually triggers it. It’s completely embarassing whatever it is.

I son’t think it’s his hearing. I think’s more that he didn’t have it sitting in traffic like I typically do. It starts ringing/humming/groaning when I’ve been in traffic a while and not at a consistent speed.

Does it do this at idle? If so, can you get out and open the hood and see where it is coming from?

If it sounds like a sheet metal rattle or groaning, it could be the heat shields on the exhaust system. If it’s a ringing (almost like a bell) it could be the end pieces of the flex pipe that have broken off and are rattling up and down the pipe. If that’s it, you fix it by either tightening the clamps, putting on new clamps, or cutting off the loose pieces.