I seem to be having the most problems with my GLK out of everyone, lol. Or, I just complain the most.

Anyway, these past couple of days, I've been hearing some strange wirrey noise coming from my car. It sounds like a small jet is starting up somewhere inside it. It doesn't follow RPM, but it follows speed, and is audible past like 30MPH...

I first noticed it when I was driving w/ the AC on and radio playing. I turned off both one by one, thinking that it was just a bad electrical connection to the radio or the AC was just making a little noise from the ducts, but nothing changed.

I talked to a buddy of mine, and he said that it might be that I need to change out my front diff fluid, but after 17,xxx miles, I doubt that's the issue. I also thought that the sound can be the result of something caught in the brake shield, or inbetween the caliper and the rotor, so I tried some hard braking a couple of times, but nothing changed.

Anyone experience anything similar to this or have any thought to what it might be?

TYIA

 

buddy, trust me, I have the most problem with my GLK. it's been in the shop for a total of 10 days and counting (its still there right now) for a variety of problems and i picked it up @ the end of Feb, lol

Its in there right now cause the cooling fan comes on max since the engine temp goes close to 100 degrees for no reason. Coolant level's fine and everything. You might want to keep an eye on your temp guage to see if it fluctuates like mine did. Normal temp for these cars is 90 and it should NOT fluctuate much unless you are pulling something. During normal driving (10 minutes) mine would shoot up to 100 and the aux fan would go nuts.

I have a B class as a loaner and what surpirsed me is the inside is more roomy than the GLK, lol. If i'm lucky i'll get the car back today but at this stage i rather they just fix it properly..

 

Blegh, that sounds awful.
I haven't had any overheating issues, so I guess I'm alright w/ that category. My temp. does fluctuate sometimes, but it goes from 90 down to 80, if I'm cruising at one speed for a short while, so I don't pay much attention to it because it's just that the tranny doesn't have to shift gears when I cruise at one speed.

 

Do you hear it 20 seconds after you first start the engine? Can you video tape or record the sound and post it?

 

I have it about 20 seconds after starting. I think it is normal. Sounds like a pump or something.

Do you know what it is?

 

Have they checked the trim levels?

 

Yes, it's completely normal. There are several servo's that kick on.

 

It's too quiet for a video camera to pick up, but I hear it whenever I'm driving now. Whenever I coast past speeds of 30MPH, here comes the noise. It sounds like something rubbing against metal (like something rubbing up against my rotor), but I can't isolate the sound.
I thought it was my belt and it was off balance a little somehow, but I inspected it, and nothing seemed to be off.

 

As I am no mechanic, and our GLK don't have the problem, I guess I shouldn't respond. However does the case tease my (only brain) cell, so I've tried to isolate the system which most likely is the cause, based on your findings. My taughts are that the problem is in the drivetrain somewhere, as it is speed-related rather than RPM - and then I am stuck.

A "wild shot in the dark" is that the problem could be related to the tires, given you have 17k miles+ on the ODO, and the tires are not replaced. Your description: "(like something rubbing up against my rotor)", does not point in this direction, however might it be a trial to drive the car on different roads, paved, gravel etc, to watch for any change of the pattern of the noise.

 

Bring it in for inspection... have your SA go for a little spin with you in the car.... that's the only way without actually hearing the noise.

Good luck!

 

I guess I'll take it to the service department this week.

I'll keep you guys posted.

 

I had somewhat a similar issue from 60kmph but i was easily able to identify this as wind leakage noise. Turns out there was a panaromic roof panel not fixed properly. It was eventually rectified under warranty.

 

ya my vote is on wind leakage...

 

I noticed over the weekend the sound got louder... I don't know about wind leakage anymore...
I'm going to go to my dealership in a few hours and having them check it out.

 

So, I took it to the dealership... Absolutely no change at all.
They replaced the idler pulley because there was a ticking noise at idle, but the winding sound IS STILL THERE and it's driving me crazy.
They keep insisting that it's wind noise, BUT IT'S NOT WIND NOISE.
I spent like 4 hours there and drove 2 different GLK's with the tech, and it was clear that they had WIND NOISE, not MECHANICAL NOISE. It sounded nothing like the noise in my car, and it was far from being as loud as my car.
The tech lowered the bump stops on the hood a little and put lube on the weather stripping under the hood to prevent any "wind leakage". No difference. The noise doesn't sounds like wind at all, it sounds mechanical.

As a little reassurance that I'm not going completely mad, I stopped by the Gintani shop and I have Alex (some of you who also drive BMW's might know how AMAZING his work is) drive my car. After 5 minutes behind the seat of my car, he said the noise is CLEARLY not wind noise, and it's a mechanical problem.

I guess I'm just going to have to keep going back to the dealership service department until they realize that they're going to have to dig deeper than just "wind".

 

It's LA dude! Find another dealership and start over. Idler pulley...!

 

I know, I laughed too... But it was ticking at idle, so I'll give him that. I just laughed at the fact that they expected all of my problems to be solved w/ the replacement of the idle pulley.

 

If your only hearing it at a particular speed, its possible that you have some loose plastic underguards or mud flaps which due to the winds at that speed tends to grind against some other mechanical object or wheels creating that sound..
If this isnt the case, you could probably ask someone to drive your car.. you could sit in the back seat and try to locate the source of the sound.. either top.. bottom or sides of the vehicle..

 

I hear it after a certain speed: 30MPH. And I'm guessing is because up to that speed, the noise of the car accelerating muffles the whining pitch, because in a quiet neighborhood, I can hear the winding if I'm going let's say 20MPH, whether I'm coasting or braking.

I took it back to the mechanic today, and he just doesn't know what's up w/ it. He says it doesn't sound like anything that could be potentially detramental, but he can't figure out what the noise is. We hoisted up the car (lifting the wheels off of the ground) in the service bay, and accelerated up to 30MPH. Of course, the sound of ESP trying to slow down the car was present, but the winding noise wasn't there.

I'm convinced that the noise had something do w/ the road now, but it STILL doesn't sound like wind noise.

I unno, I'll stop by another dealership later because I just don't like driving w/ a small 747 in my car and I'll get a 2nd opinion as to what the noise might be.

 

The sound is even louder now... EXCELLENT.

Also, when I started up the car, error code said that my two front SRS airbags were malfunctioning and I needed to go to a mandatory maintenance...

I restarted the car, and the message was gone, and it wasn't even in the maintenance message list.

I guess I have to make another appointment...

 

Well, the louder it gets, the easier it should be to find.
Plus you can ask the dealer to take your name off the crackpot list......

 

So I tried to pay no attention to the sound for a little while. It got louder, A LOT louder. I finally took the car in for service just 'cause I couldn't turn the other cheek anymore.

Turns out, it was the transfer case. They're going to replace it under warranty, so I can live in peace.

Wind noise... LOL.

 

Good info. My GLK does the same thing. Yours is 4matic also right? I hear the sound coming from the front of the car and it's definitely 'mechsnical' sound. Transfer case sounds right (I was going to guess front differentials for the all wheel drive). The noise is getting louder too, just like yours. Wonder how many other 4matic owners have the sane issue? Well I guess it's time to bring mine in for service too. I hope they fix it the first time.

 

Yeah, it's a 4matic as well. I wanted to blame it on the front diff. as well, seeing as it sounded like a mini jet engine in the center front of the cabin. & I kinda got annoyed at how all the tech wanted to do was blame it on wind noise.

Both of the shop foremen @ my dealer were utterly surprised when they found out it was my transfer case, so I'm guessing they haven't come across too many w/ the same problem.

Good thing it's under warranty.

If they don't fix it the first time, keep coming back, or tell them that you "suspect" that it could be the transfer case, as you've heard of a similar case.

 

I'm calling the dealer right now to make an appointment. Hopefully they can squeeze me in tomorrow. I hope they also provide me with a loaner car. Anyway I'll keep everyone posted as well once I hear the verdict.