ksgirl

I have a 2004 Grand Cherokee Laredo with 133000 miles - it has an obnoxious knocking noise under the driver side dash or really high up under the hood.
If you're standing outside the truck it's hard to even hear it but inside, with the windows up it seems really loud.
We have narrowed it down to only making the noise when it's in drive. If the vehicle is in any other gear or in park - it stops.
It doesn't seem to be affecting anything in the truck so we haven't taken it to a shop yet, was just wondering if anyone else has come across this and how it was fixed???

ol"blue

Welcome to CF.
We bought our '04 Grand new, and a few years ago we were bothered by a similar issue. Turns out it was the EVAP solenoid on the drivers fender near the master cylinder. It was making vibrating into the metal fender causing the noise in a knocking fashion. The dealer fixed it under warranty by using a rubber isolator. The noise went away.
It may be the same problem you're having.