buzzing/vibration behind dash

The vehicle is a 1998 XJ with the 4.0L, AW4, 231, D30/D35. We bought it last summer. AC is great and cold but the heat barely worked this winter.

There is a buzzing sound coming from behind the center to passenger side dash when speeds reach 45-47 mph with the windows down. You can turn on the AC and it doesn't quit. It is worst between 45-60 mph. Any idea of what could be causing this? It sounds vibration related.

Dash rattles are fun. I can only tell you what you already know, it's something loose. Thumping on the dash is misleading too, you'll get all kinds of little squeaks and rattles that you never hear otherwise sending you chasing your tail.

Good luck and have fun.

I have/had a buzz in that general area as well. I pulled the bottom of the center bezel (down by the 12V outlets) just barely out of the retaining clips and the buzz went away. I still need to put some felt pads on the contact areas and pop it back into place, but it is quiet for now. You may want to give that a try. Only takes a second and if doesn't work, at least you know what isn't causing your buzz.

My buddies tacoma had a horrible dash rattle. I folded up a little piece of paper and wedged it between the dash and the windshield, problem solved.

I don't think it is the dash as I have laid my hands on it trying to see if the sound quits and it doesn't.

I used the term buzzing but squealing might be another word to describe it. We are going to drive it this morning so I will see if I can isolate the sound further.

Thanks for the ideas so far.

Well, as an update we finally got a chance to try and locate the noise. We found that the front winshield rubber seal didn't seem to fit great. We started messing around with it and the sound stopped.

I attend church with a guy who works at a glass company so I asked him about the possibility of the gasket creating the noise and he said he has seen it many times. He recommended some silicone on the back of the gasket where it touches the roof. So we will try that to make sure the noise doesn't come back.