Silvir00

Hi, I'm curious if any other members experienced this unique and troubling phenomenon of an intermittent and variable hooting sound that occurs quite frequently during every drive. There is no one factor that provokes the sound to appear, it simply occurs on every drive. It can be lound or low sound at times. It doesn't effect the drive or performance, it is just extremely annoying!! After hearing it hundreds of times, it becomes an unwanted preoccupation hearing and listening for it. If any other members have experienced this same phenomenon, I would be very appreciative of their feedback.
Brad. Going forward, yes I have checked for owls underneath my hood. Haha

Beeblet65

I am guessing you are hearing the turbos spool. - I hear it all the time on mine.

Silvir00

Hi
that's a reasonable assessment but all my other cars are twin turbos and am quite familiar with that sound and like it. This is unrelated to throttle position. It makes a whoooo sound intermittently. It’s not the release of turbo back pressure. I wish. Sounds exactly like an owl hooting as weird as that may sound, once you hear it you would smoke and say where!s the owl?? Sooo bizarre and soooo frustrating on a brand new vehicle, thanks. Brad

Beeblet65

Hey Brad - By it not being related to the throttle position does make it another case.

My thinking with the turbo noise was that there is just a metal shield over them which can resonate the noise. - The current G63 5.5L Biturbo engine has the turbos much lower which is why it is not as apparent.

Silvir00

Ya I get what you’re saying now. With the new hot vee configuration this can be very much what it is. Some kind of weird resonance. That sounds reasonable and probably the best advice I got so far, I will see if I can get a mic under the hood and see if I can catch the noise above the ambient engine sound. Good thought. Thanks Brad

twist-a-grip

I kinda took a dig at you the other day because you made it sound like MB should give you a new truck - which I still say is quite ridiculous!! That being said, I drove my 4x4 on Saturday and may have heard the owl. However, the owl in my truck happened right after the shift from 1-2 from a stop. If I floored it, no hoot and no hoot after any other shifts that I could hear. With a regular, normal takeoff speed, it would hoot one very short hoot. I have no doubt, it has something to do with the turbos and is not a HVAC and tranny issue - just a sound the motor makes under certain scenarios that gives it a little character.

If you think otherwise, go to your dealer and invite the service manager for a quick spin and point out your hoots and see what they think.

Silvir00

That was my wife's post. The G550 is her truck and frustrated with the truck. Of course MB wouldn't give a new truck. They'll keep on working for a solution until they find one.

I agree, its probably a turbo issue. I'll be taking the truck in this Friday for a road test with manager and technicians. It didn't make this noise right off the bat when she got the vehicle. It started about a month later when an engine light came on and MB had to replace the fuel sensor. The noise started after that.

rhyno

My 4x4 2 makes a hoot sound sometimes. It comes from the roof spoiler. I think it’s a crosswind that gets forced through the spoiler and makes the odd noise.

coopersport

I have the same problem on a G500 (not turbo), sometimes and usually with AC On when I reach 60MPH the hooting noise starts, is a speed related but not from wind, it doesn't changes if drive very close to a truck, last summer I drove from Baltimore to NY and it was insane, in winter no problem.....

Limey Hooligan

If it's an intermittent hooting/air sound not related to throttle, the only time I've had that is when the air system on the contour seats failed. Being air bladders connected to an air pump (under the passenger seat, I believe), it can make an intermittent compressed air noise if the system piping has a leak and the pump goes off and on to try and maintain air pressure. My $0.02.

helinomad

My 2017 G550 does exactly this but only when I lift off the gas. Doesn’t seem to be an issue. Possibly turbo related. I think it sounds cool honestly...

efathalla

I have the same noise in my 4x4, and I was wondering what is it, I don’t think it’s turbo related, but I have no explanation for it.