I have an 04 Excursion with the 6.0. Every time I apply the brakes I get a loud drone/vibration noise (very noticeable when stopped). Took it to the dealer and they advised that my exhaust system needed to be reground/realigned as the noise was from the exhaust. Stated it would cost about $179-$225 to fix. I was told it wasn't a part issue, just a realignment issue. I didn't want to spend that much so I decided to forgo that and try to fix myself. I got underneath and did not see any problems with my mounts. With the truck running, as soon as I pull down slightly on the catalytic converter, I replicate the loud drone. From what I can tell the pipe coming from the turbo goes behind the motor and down towards the catalytic converter, that pipe is solid and doesn't move. The rest of the exhaust is supported by mounts, all look fine. Makes me suspect something else besides an exhaust reground. Do I just have a bad catalytic converter, is there anyway to test it? If in fact it is an exhaust reground issue; my excursion has 84000 miles, should I look at getting an aftermarket exhaust? If so what brand or recommendations? My truck is stock and I tow a Travel Trailer. I don't want to go too crazy with MODS.

 

Did you check for a bad motor mount?

 

No did not check for that. I will take a look, I don't suspect that though.

 

OK, nothing wrong with the motor mounts... Can anyone help me???