mbartholome

Have less than 1000 miles on our new 2016 GL450 and have noticed a very intermittent noise inside the cabin. Sounds like a high pitched hum. Has happened in town 3 times (20-30 MPH) and on the highway (75 MPH) once. Not in the radio as I turned it off the two times I was driving and noise persisted. Have not figured out what makes it go away but it does after 5-10 seconds. Called dealer and they said no other customers reporting issue and no TSB on it either. Hope someone else has had this issue and resolved it as it will be very difficult to diagnose at dealership w/o them putting a lot of miles on the vehicle.

I hope this is an isolated incident as well as we got rid or our 2015.5 Cadillac Escalade ESV due to the numerous problems, noises, rattles in that vehicle.

Count Laszlo

Air suspension pump? It whines a bit I believe. I hear it when I get home. But I'm learning mine right now so don't know for sure.

Slaynx

Record the noise and post it here?
I use dash cam that record all frontal traffic and as well as cabin sound. Or you can get an app on your phone to record sound. Just leave the app running until it catches this pitch.