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I have a knocking noise from the front of the car - not sure where exactly but it is definitely not inside the car and sounds like it's from the front wheels/suspension area.
The noise is very clearly heard when driving over rough road at about 10 mph - faster than that and it gets drowned out by road noise etc, but the noise is still there.
Its quite hard to explain without actually hearing it and unfortuatly I can't get a good video of the noise - but this isn't just the odd rattle/knocking noise, it's constant whilst going over rough road such as cobbles - once it smooths out you can't hear it.
I took it to the dealership a couple of weeks ago for a map update and asked them to take a look as I'm positive it's not normal.
They had the car for 5 days (Monday - Friday) and this is where I got a little annoyed!
Now they did update the map and it took about 4 hours - they did this Tuesday morning - the car then left the workshop and was sat in their car park until Friday!
I happen to know this because I have a dash cam which they didn't unplug - I can access the camera remotely and so also happen to know that once it left the workshop on Tuesday it did not move until I collected it on Friday.
My car never went on a lift/ramp and so never left the ground - yet they told me that they'd taken a look and found nothing wrong!
I didn't tell them I knew all of this and I will be taking the car back at some point when I get time - I will also request to go out on a test drive with a technician.
Anyway, back to the question - does anyone know what this could be?
Boy those guys hate dashcams, but only because it catches them doing or not doing stuff they don't want you to know about. I know BMW dealers are requiring dashcams to be removed before servicing and claiming it's to protect their trade secrets. LOL.
Going back to them sounds like a waste of time. If you call them out with the dashcam, you'll get the "sneezer muffin" treatment from now on. And if you don't call them out, they'll just do the same no-action over and over.
I would take it to a shop that just does alignments to take a look at it. Those guys are experts at finding suspension issues because they can't get alignments to work if there's something loose in the suspension. It could be any number of things. Sway bar bushings that have gone bad have been a common one. Something loose with a brake caliper could do that too. It could be a bad control arm. A bad ball joint. A bad shock mount. Or something loose in the engine bay or a loose panel.
You should always mention what year and how many miles on your vehicle.
Last edited by 2020GLC300; 09-26-2019 at 04:41 PM.
Sounds like this is a car still under warranty. If that's the case I would go to another stealer and start fresh. Arrange for an appointment to go for a test drive with a tech as a first step, don't agree to this "leave the car with us" stuff. Once the tech has identified and noted that there is a noise, they're on the hook to fix it.
If the car is out of warranty, 2020GLC300's suggestion is probably the way to go. Good luck.. .
Hahah, trade secrets - well I think Mercedes' trade secret is to leave the car and hope the problem magically fixes itself!
Yeah I wouldn't ever call them out on it although I would love to! - Something like this shouldn't happen at any dealer, but this happened at their new flagship dealership in Stockport where you'd expect the best.
Sorry I should have - bought new in December 2018 and has done almost 18000 miles so definitely still under warranty.
I will definitely try a new stealer and make sure I go for a test drive with a tech this time.
Failing that I guess I'll have to do what 2020GLC300 suggests and find an alignment shop for them to take a look - then get Mercedes to fix it...
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
How many Km or miles ?
As a rough guess I would have both drive shafts checked.
Sort of sounds like a drive shaft failure - not always easily ID, but need to be put on a hoist and inspected.
Good luck, let us know how you get on - yes I would try another Dealer, or pre book technician drive. Some Teck’s has their own special route they drive to try and replicate sounds, even in suburbia.
How many Km or miles ?
As a rough guess I would have both drive shafts checked.
Sort of sounds like a drive shaft failure - not always easily ID, but need to be put on a hoist and inspected.
Good luck, let us know how you get on - yes I would try another Dealer, or pre book technician drive. Some Teck’s has their own special route they drive to try and replicate sounds, even in suburbia.
Hi,
The car has done almost 18000 miles - is that not a bit early for drive shaft problems?
Saying that it’s a bit early for any problems...
Will definitely get booked in with a tech drive and report back!
I had a similar problem a couple of months ago, but my car is 56000 km. The noise was from the front part of my car and was appearing when the road was not very good. Please find attached picture with part which was damaged. I replaced both and noise was disappeared.
I had a similar problem a couple of months ago, but my car is 56000 km. The noise was from the front part of my car and was appearing when the road was not very good. Please find attached picture with part which was damaged. I replaced both and noise was disappeared.
Thanks for that info - I’ll get under it this weekend and see if I can find anything.
I’ve a friend who may be able to take a look with me who knows a bit more than me - if we find anything then it’ll be the dealers job to replace!
I had a similar problem a couple of months ago, but my car is 56000 km. The noise was from the front part of my car and was appearing when the road was not very good. Please find attached picture with part which was damaged. I replaced both and noise was disappeared.
Is that the sway bar? Wouldn't surprise me. I mentioned that as a common culprit above.
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
Some owners reported mystery rattles in cabin, difficult to isolate.
A few have placed electrical tape around the locking pins that hold up the rear seats in lock - appears some slack in the locking system allowing pin and catch to rattle / vibrate - fixed their noise issues.
May be worth a look.
My new GLC300 had a creak start around the 1k km mark. A firm jiggle of the drivers door a-pillar panel (covering the airbag) and it went away. It wasn't a loud squeak but it was driving me ding bats.
You kinda sound like the type that would buy a can of that spray for fixing squealing old fan belts instead of changing an old belt.
Was this comment absolutely necessary? Decorily did put 'cured' in inverted commas which clearly implies that this was a temporary measure. Being charitable, maybe you missed that.
Sorry for all the hurt feelings. I was just trying to be helpful because lubricating rubber suspension bushings is a really bad idea, and speaks volumes of the poster's knowledge and approach to maintaining cars while trying to pass off "expert" advice. I won't be buying a used car from her.
I was just trying to be helpful because lubricating rubber suspension bushings is a really bad idea, and speaks volumes of the poster's knowledge and approach to maintaining cars
Why is lubricating rubber bushings such a bad idea!
The only thing that remains now is a rattle that happens over any sort of rough road or pot holes.
It’s definitely an interior rattle but I can’t for the life of me figure out where it’s coming from, possibly in the dash somewhere![/QUOTE]
Hi,
Has this issue been solved? This issue annoyed me seriously too. I tried many different ways to solve it but it didn't go away, I damp the car inside and out, I damp inside tires, I took off the stiffener bars. What was helping me is to turn on the music loud.
In my thought, there is one more source that could create such rattling noise is from the front drive train (unit). Since the vehicle is designed for torque distribution of 60 rear and 40 front. What is happing here is that the front drive train is loose (lazy or hanging you may say) because there is no load while driving so the gears inside the diff or the spirals from the driveshafts are loose and knocking that caused the rattling noise.
I don't know if anyone tried before to remove the rear prop shaft so that it will act as a front-drive car to see if the noise is still there or not. (to be honest, I don't know if the car will drive without a rear prop shaft as there is no center diff lock). Maybe putting much smaller wheels at the rear with engaging the slip sensor switch is a better way to test.
Perhaps putting a thicker diff oil will help as well.
Maybe someone here can help me with my thought. Thanks
09-26-2019, 01:54 PM
