Hello fellow posters and X167 owners.
I'm posting in an attempt to help the dealer resolve an issue with my 25 GLS 450.
I purchased the vehicle back in September near Atlanta. On the drive home from the dealer I got on the interstate for my first high speed driving and discovered a buzz in the passenger side front corner of the headliner by the sunroof.
The buzz sound starts at about 60 mph and increases volume with speed. It is annoying.

I immediately returned to the dealer and they were very apologetic and provided a new loaner immediately. 5 days later they returned the car with the issue resolved.
The fix was a total sunroof replacement, however they damaged the headliner among other things in the process. My guess is the tech was under pressure and in a hurry, but still not acceptable. They were apologetic once again and ordered a new headliner and other items which took some time to come in. The dealer came to me and provided a like for like loaner and the headliner was replaced among other items, which took 7 days.

The car has been great up until this past weekend when the buzz returned with a vengeance. I suspect it may have something to do with the cold snap we just had here in the South.

I've posted on a FB page and have heard of other owners experiencing similar issues. Some resolved some not. I have a feeling the dealer service dept. has no idea about how to approach this.
So here I am reaching out on any forums I can to see if I can throw the service techs a bone and maybe point them in the right direction to get a permanent resolution.

Short video is attached.

Anyone have any experience addressing this issue?

Love the car other than this one issue.

 

I had the same problem with my 24 GLS. The culprit was the luggage rack where it attaches to the roof just above the windshield on the passenger side. I’m not sure what they replaced but it worked for a few months. Unfortunately the noise is back. I’ll take it back in after Christmas but, until then, strategically placed black electrical tape will stop the noise. Yeah, I have to use tape to make wind noise bearable on a $125k vehicle. . . .

 

The new G45 (X3) has a pano roof that can't be opened. Perhaps this is where everyone is headed, whether we like it or not!

 

Finally received our car back yesterday. So I'm not 100% convinced the issue has been resolved but I will report on what currently has been reported to have resolved the issue.
The cause was traced to a deformed drip rail which allowed wind to get underneath it and therefore act like a reed on a wind instrument and therefore 'buzz.'
The shop was able to trace it to the specific location of the buzzing by using compressed air.

They removed the right roof rack rail and the associated suspect drip rail and replaced it. I'm not an expert at reading MB service statements but it appears to be trim bar part# 167-690-16-09.
This part took some time and high level negotiations to get in and ended up with the dealer keeping the car for a total of 33 days this visit and now an accumulated total time of 45 out of service for this issue.
We've owned the car for a total of 109 days so it's been out of our hands for this issue over 40% of the time.
It should have been a week shorter but the first part they received in was damaged and unusable. I think damaged in transit because if I'm being told correctly the part was pulled off the assembly line of available parts?
The part was reordered and the second part is what is on the car now. The part is no longer on back order and is now readily available.

I've been patient during this entire process, mainly because I really like the car other than this issue. Thankfully the dealer has been apologetic and supplied me with a near equivalent loaner this entire time.
Of course it was emblazoned with the dealer's info in the back window, which is sort of embarrassing after a couple weeks, but no biggie.
MBUSA and their buyback service contacted me in the interim in addition to the dealer trying to find me an identical or near identical replacement. The buyback process is a 4-6 week process and I'm not super enthused on that because I like the car.
This entire time it's sort of been a race between which process would get me a car first.
The dealer will apparently have a near identical car in later this week as an available path to resolution. It apparently has a few options that mine doesn't have but is also missing one that I wanted which is 5-zone A/C.
My wife is ready to go with the new car because it hasn't been taken apart multiple times and why not when offered. We would seldom occupy the 3rd row so maybe the 5-zone isn't really needed.
But provided the original one is fixed I'm sort of leaning towards keeping it rather than the hassle of switching everything over.

I hope all this helps if anyone is suffering with the same issue.

 

Glad to hear there is a resolution! The dealer is doing all the "right things" so hopefully they get you into something you want sooner than later!

 

I agree. Based on the OP's update, the dealer seems very reputable thus far.

 

I can confirm we are having the same issue as well, brand new 25 gls450. The rubber drip rail on the passenger side appears more pliable than the drivers side for whatever reason and we are getting significant noise at the 70-75mph mark on highway driving at cold temps. Have not tested car in warmer weather yet, but possibly /hopefully will resolve based on what I'm reading.

Any solutions on what kind of 'caulk' or tape I could put on the leading edge to prevent the reed effect from creating the buzzing sound that would last and not be tacky?

 

I used black electrical tape on mine to stop the noise until it could be fixed. It took my dealer 3 times but, fingers crossed, they may have finally succeeded. The wind had to be just right or I had to be traveling in excess of 75 mph to hear it consistently. It was frustrating when I took the lead tech out to hear it (“if I can’t duplicate it, they can’t fix it”) and it wouldn’t make the noise. It was equally frustrating when I was told it was fixed but learned that they can’t test in excess of the speed limit, which meant they really didn’t test it. If it makes the noise again, I’m going to fill the gap with black caulk. I’m sure that will solve the problem but it’s sad I’d be driving around in a bucket-list vehicle that has to be caulked to stop the wind noise.. . . . .

 

Just to throw in, the R231 SL-Class is not immune from this type of problem. With the SL the problem is with the A pillar cover on the outside vibrating and causing the buzz. You may want to see if your cover is loose.

 

No issue with my pre-refresh GLS X167. However, pano roofs should be eliminated altogether, or at least be offered as an "option" not standard. If they must exist, I would prefer them to be rigid and fixed in place and not open at all.

My previous 8-series BMW had a carbon fiber roof on the outside, and an Alcantara headliner with thick insulation underneath. That roof was fantastic – quiet and had no heat issues whatsoever. I would gladly pay more for a solid metallic roof over a pano roof. My current 7-series has a pano roof but at least it's a rigid/fixed one. Even then, I went ahead and applied a glass-black vinyl wrap on the outside to eliminate and radiative thermal bridging which even the interior fabric covers don't fully block on very hot day. I just don't like pano roof.
Same for our GLS... luckily the interior is ivory, and the pano roof cover is ivory too so heat is manageable and it's closed all-year long. However, each time I have the the roof cargo box up there on highways, that air turbulence noise becomes unavoidable with the pano glass roof. Truly useless and I don't get it why all manufacturers thing it should be a standard feature that we can't opt out of.

Note: OP thanks for posting the fix. Looks like the dealer in your 2nd post finally addressed it? Would you mind sharing the service notes and confirm the part number that was changed with us?

 

Here's the specifics summarized from the service notes that I have.
889950 Drip rail on right side replace (I think the part number is 167-690-16-09)
681611 Roof trim remove/install vehicles with panoramic sunroof
Right side roof trim deformed.
Performed road test verified wind noise.
Traced wind noise using compressed air in shop.
Found right drip rail to be deformed.
Heavy wind raising the drip rail causing the wind noise.
Replaced drip rail.

I will also add that after our full experience with this specific vehicle issue we ultimately accepted the dealer's offer for a replacement GLS. We actually received a near identical spec with some additional options for a lower cost.
Not because the issue wasn't resolved, because it was my belief that the repair did successfully resolve the buzzing however, we were not pleased with the end result.

To address the issue the headliner had been removed multiple times and replaced once due to damage by the service department. Additionally, there were multiple damaged or missing attachment tabs.
It is my belief that the vehicle had been left open, likely windows down in the shop for greater than a month while waiting on parts.

So essentially the interior of our brand new $100K+ vehicle had the look and feel of a well used rental car and did not meet our expectations for what a 'new' car should be and this was the driver for our decision.
I'm right at a year removed from the issue at this date and I stand by the decision being the correct one.

We lost the 5 zone HVAC in the swap but got rear shades in the new model and I'm much happier with the result, plus the dealer gave us a nice check in the trade to soften the blow and gifted us roof cross bars as well. In the past year we've had maybe 3 instances of having people in the rear seat with no complaints on temps but have used the shades much more often.

Overall the new car has been trouble free and I'm please with the dealer's sales department and would buy from them again. The service department at this dealer is another story.
They were a contributor to many of their own problems with rushed and poor repairs and bad quality control.

At this point I'd call it a theme with the service department after having multiple models serviced, (GLC and GLS) and I've grown accustomed to doing close inspections of cleanliness following any services.
In fact during my one Service A this past year I had to get service managers involved because the seat and armrest were dirty following service.
Again the dealer management stepped up by resolving it quickly (luckily) and now owe me a full detail on my next service to make it up to me but none of this should be happening at this level and the problems are easy to resolve if managed correctly.

I would imagine my old low mileage original GLS with the buzz and botched repair job is probably a nice loaner at my dealer or another somewhere. Time will tell should I get it someday as I basically have the VIN memorized at this point.
Hope this helps.

 

Sorry for your experience but it does sound like there's a silver lining to it! I hate when the good sales experience doesn't line up w/the service experience. We can't have it all!

 

Yeah, certainly nobody is perfect. But it's such an easy fix and techs aren't working on Nissans so come on and step it up with the cleanliness and care.

I've made suggestions to the dealer reps, such as having the advisors move cars rather than techs for anything besides a test ride but to no avail.
One of these days someone is going to have serious damage to an interior that can't easily be managed.