Thud after coming to a stop
#1
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2014 GLK250, 1983 Caterham super 7
Thud after coming to a stop
Had my '14' GLK250 in for a service 'B' today. One of the issues I raised was the thud/clunk a few seconds after coming to a stop. The service writer and I went for a test drive and miracle of miracles. The problem actually presented itself instead of hiding for the test drive. They put in the software update that was mentioned on another thread (three things you don't like about your GLK) about this and other issues. The tech said it still had the issue when he drove it after the update. I didn't notice it on the way home.
Now, The cause of the issue (as explained to me by the tech) is the fact that the MB auto trans has a locking torque converter for better efficiency. Upon stopping for more than a set amount of time at a light. The computer will back off the torque converter completely (almost like a neutral position) while in gear to ease the load on the engine. When the load is released the driveline suddenly 'relaxes'
It's a similar (but much much less) effect as having a manual trans and dragging the clutch a bit and pushing the gear lever into neutral thus causing the drive shaft to ring from the backlash on the ring & pinion gears when torque is suddenly released on the driveline.
Now, The cause of the issue (as explained to me by the tech) is the fact that the MB auto trans has a locking torque converter for better efficiency. Upon stopping for more than a set amount of time at a light. The computer will back off the torque converter completely (almost like a neutral position) while in gear to ease the load on the engine. When the load is released the driveline suddenly 'relaxes'
It's a similar (but much much less) effect as having a manual trans and dragging the clutch a bit and pushing the gear lever into neutral thus causing the drive shaft to ring from the backlash on the ring & pinion gears when torque is suddenly released on the driveline.
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#3
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350 GLK, C280
Do you hear this thud when you take your foot off the gas and the wheels are driving the engine (no brake) such as coating down a hill? Do you get it when you go from coasting to power on? Even if the explanation is correct, there must be excess play in a CV or other joint to make a thud sound that you could hear inside.
The 2015 350 GLK probably has the engine turn off system so you would not need to release the converter with the engine stopped.
The 2015 350 GLK probably has the engine turn off system so you would not need to release the converter with the engine stopped.
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2014 GLK250, 1983 Caterham super 7
Just when I come to a stop and I'm depressing the brake pedal. The thud is barely audible. It's more like a single bass note and you feel it more than hear it.
I'm not worried about it in the least as it does not sound like a mechanical issue like when one has to much ring & pinion back lash.
I'm not worried about it in the least as it does not sound like a mechanical issue like when one has to much ring & pinion back lash.
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2014 GLK250, 1983 Caterham super 7
bop11,
MB knows what causes the sound. Please see the second paragraph in my first post. It's a transmission programing issue. There is a software update for this issue. LI27.19-P-56898
MB knows what causes the sound. Please see the second paragraph in my first post. It's a transmission programing issue. There is a software update for this issue. LI27.19-P-56898
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2014 GLK250, 1983 Caterham super 7
An update. Just took the GLK out for a spin through downtown Walla Walla. It would always make that noise when pulling up to stop at a light. It has done this since buying our GLK in May 2014. Today I never heard that noise under the same scenario. The one time it did make that noise was when I was just starting to move after being stopped and just a second later had to stop again after very momentarily getting on the throttle.
So it seems that the transmission software update was (mostly) successful.
So it seems that the transmission software update was (mostly) successful.
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#8
We just purchased a 2015 GLK250 Bluetec and I immediately noticed the same thing. About 3 seconds after coming to a stop, it feels like the car has just been tapped on the bumper from behind. Good to know there's a service bulletin on the subject; we'll have it looked into at the next visit to the dealer.
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kuuner (07-21-2022)
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2014 GLK250, 1983 Caterham super 7
Mine came back not long after I posted that it seemed to be fixed. I guess it's something I need to get used to. As it's caused by the torque converter going into a neutral condition I'm not going to worry about it.
But folks might still want to have that software update done as it will at least have your issue logged into MB's system before the warranty expires. If it does become an issue later. It gives you the opportunity to have it looked at under the warranty due to it being logged as an existing issue.
But folks might still want to have that software update done as it will at least have your issue logged into MB's system before the warranty expires. If it does become an issue later. It gives you the opportunity to have it looked at under the warranty due to it being logged as an existing issue.
#11
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Greetings all, I too have the soft thud several seconds upon coming to a stop. Just picked up our CPO 2014 GLK250 last week with 48K on the clock.
First service scheduled in a few months, I will inform my service advisor about an available update. Thank you kindly, super7pilot, for relating your experience. I'm mostly relieved it's probably nothing serious, although I would like to not feel/hear it from a $30K luxury CUV.
First service scheduled in a few months, I will inform my service advisor about an available update. Thank you kindly, super7pilot, for relating your experience. I'm mostly relieved it's probably nothing serious, although I would like to not feel/hear it from a $30K luxury CUV.
#12
resolved by dealer!
I reported this issue earlier. Our GLK250 now has 25000 miles on the clock and was due for maintenance, so I reported the "thud" to the service advisor when I dropped off the trucklet. To quote the service notes verbatim:
I hope this helps others with the same issue. Given the amount of labor in the description, it's definitely something you'll want to have done while still under warranty!
CUSTOMER STATES EVERYTIME AT A STOPLIGTH (sic), WAIT 3-5 SEC. SLIGHT JOLT.. LIKE SOMEBODY HIT REAR BUMPERGENERAL MAINTENANCE.
CAUSE: .
412390 R&R SHAFT & APPLIED /GREASE
309 WMN
25502 GREASE PROPELLER SHAFT/GEARING. TEST DROVE VEHICLE, WAS ABLE TO VERIFY AFTER EVERY STOP APPROXIMATELY 5-7 SECONDS, VEHICLE WILL GIVE A SLIGHT JOLT.
PER LI27.19-P-056898. R&R UNDERPANEL, CATALYST, SUPPORT BAR, O2 SENSORS, HEAT SHIELDS, VIBRATION DAMPER FROM TRANSFER CASE. REMOVE PROPELLER SHAFT, APPLIED GENEROUS AMOUNT OF GREASE TO SHAFT/GEARING AND SEALS. TEST DROVE VEHICLE AFTER REPAIRS, FOUND NO MORE JOLTS AT COMPLETE STOPS.
So it seems this is a known issue with a service note (LI27.19-P-056898 seems like a service note number.) Interestingly, there is absolutely no mention of a software update on the service invoice, just the mechanical changes noted. I can confirm, whatever was done took care of the problem. CAUSE: .
412390 R&R SHAFT & APPLIED /GREASE
309 WMN
25502 GREASE PROPELLER SHAFT/GEARING. TEST DROVE VEHICLE, WAS ABLE TO VERIFY AFTER EVERY STOP APPROXIMATELY 5-7 SECONDS, VEHICLE WILL GIVE A SLIGHT JOLT.
PER LI27.19-P-056898. R&R UNDERPANEL, CATALYST, SUPPORT BAR, O2 SENSORS, HEAT SHIELDS, VIBRATION DAMPER FROM TRANSFER CASE. REMOVE PROPELLER SHAFT, APPLIED GENEROUS AMOUNT OF GREASE TO SHAFT/GEARING AND SEALS. TEST DROVE VEHICLE AFTER REPAIRS, FOUND NO MORE JOLTS AT COMPLETE STOPS.
I hope this helps others with the same issue. Given the amount of labor in the description, it's definitely something you'll want to have done while still under warranty!
#13
I have the exact same issue and suspect that it is the transmission doing something and not the engine. My local dealer is hopeless so I am curious what the fix is or if it is just the way it is. I also have a C63 that in sport mode going down to 1st makes a much harsher clunk that is "normal" according to the dealer..
Ed
Ed
#14
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I reported this issue earlier. Our GLK250 now has 25000 miles on the clock and was due for maintenance, so I reported the "thud" to the service advisor when I dropped off the trucklet. To quote the service notes verbatim:
I hope this helps others with the same issue. Given the amount of labor in the description, it's definitely something you'll want to have done while still under warranty!
CUSTOMER STATES EVERYTIME AT A STOPLIGTH (sic), WAIT 3-5 SEC. SLIGHT JOLT.. LIKE SOMEBODY HIT REAR BUMPERGENERAL MAINTENANCE.
CAUSE: .
412390 R&R SHAFT & APPLIED /GREASE
309 WMN
25502 GREASE PROPELLER SHAFT/GEARING. TEST DROVE VEHICLE, WAS ABLE TO VERIFY AFTER EVERY STOP APPROXIMATELY 5-7 SECONDS, VEHICLE WILL GIVE A SLIGHT JOLT.
PER LI27.19-P-056898. R&R UNDERPANEL, CATALYST, SUPPORT BAR, O2 SENSORS, HEAT SHIELDS, VIBRATION DAMPER FROM TRANSFER CASE. REMOVE PROPELLER SHAFT, APPLIED GENEROUS AMOUNT OF GREASE TO SHAFT/GEARING AND SEALS. TEST DROVE VEHICLE AFTER REPAIRS, FOUND NO MORE JOLTS AT COMPLETE STOPS.
So it seems this is a known issue with a service note (LI27.19-P-056898 seems like a service note number.) Interestingly, there is absolutely no mention of a software update on the service invoice, just the mechanical changes noted. I can confirm, whatever was done took care of the problem. CAUSE: .
412390 R&R SHAFT & APPLIED /GREASE
309 WMN
25502 GREASE PROPELLER SHAFT/GEARING. TEST DROVE VEHICLE, WAS ABLE TO VERIFY AFTER EVERY STOP APPROXIMATELY 5-7 SECONDS, VEHICLE WILL GIVE A SLIGHT JOLT.
PER LI27.19-P-056898. R&R UNDERPANEL, CATALYST, SUPPORT BAR, O2 SENSORS, HEAT SHIELDS, VIBRATION DAMPER FROM TRANSFER CASE. REMOVE PROPELLER SHAFT, APPLIED GENEROUS AMOUNT OF GREASE TO SHAFT/GEARING AND SEALS. TEST DROVE VEHICLE AFTER REPAIRS, FOUND NO MORE JOLTS AT COMPLETE STOPS.
I hope this helps others with the same issue. Given the amount of labor in the description, it's definitely something you'll want to have done while still under warranty!
I also got same noise problem about 3 sec after full stopping. This noise "thud " does not come on every stop, but thud noise is frequently heard when my cold vehicle stops for the first few miles.
Today the MB advisor confirmed the thud noise came from the propeller shaft and the transmission.
MB mechanic lubricated the propeller shaft , re-program the transmission module as per TIPS ZM941010. Propeller shaft from transfer case to front axle was removed, installed to establish the finding. Checked the data bus and control unit...
I hope MB mechanic fixes the thud noise from the transmission system, and I will confirm the MB solution after few more days of driving.
Initially two other MB advisors suggested that thud noise came from torque converter to improve gas mileage by about 5%. This special gas saving feature comes with the torque converter noise problem, and this torque converter shut down noise cannot be eliminated.
Hope that is not truth, and it seems no logic to it.
I do not know what is the real cause of transmission noise.
I just want to log in this transmission noise issue in case of future warranty issues, and hopefully I am still eligible for free warranty fixes.
I will advise other MB owners to ask MB to check out any noticeable noise when your GLK 250 vehicle is still under free warranty fixes.
MB recently replaced two GLK 250 front shocks after I complaint about the strange noise from the front end during the first few miles of driving. Maybe the 2014 shocks had tight tolerance when they were cold and caused friction noise.
After the front shocks were replaced under MB free warranty , that noise was totally gone.
It is a drag to report these noises, but it will eliminate these expensive repair cost and provide you peace of mind in the long run. Report these noise problems especially you still have factory warranty.
#15
After downloading data from the transmission and sending it to MB Canada, the dealership and MB Canada finally have resolved this issue. They replaced the transmission valve body under warranty.
#16
Junior Member
Mine has been doing this as well, especially after a quick stop. I thought it was the DEF fluid sloshing. I agree with super7pilot's assessment because I have noticed that about 2 seconds after stopping I can pull on the left shift paddle and the transmission feels like it downshifts. I wonder if anyone else can duplicate that.
Anyway, I'll see if the dealer will install the software update or even knows about it.
Thanks to everyone who has commented on this issue.
Anyway, I'll see if the dealer will install the software update or even knows about it.
Thanks to everyone who has commented on this issue.
#17
MBWorld Fanatic!
Mine is scheduled for this as well. Will update once diagnosed.
#18
Junior Member
Problem solved
Mine has been doing this as well, especially after a quick stop. I thought it was the DEF fluid sloshing. I agree with super7pilot's assessment because I have noticed that about 2 seconds after stopping I can pull on the left shift paddle and the transmission feels like it downshifts. I wonder if anyone else can duplicate that.
Anyway, I'll see if the dealer will install the software update or even knows about it.
Thanks to everyone who has commented on this issue.
Anyway, I'll see if the dealer will install the software update or even knows about it.
Thanks to everyone who has commented on this issue.
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2014 GLK250, 2012 C250 Coupe
Took the 2014 GLK250 in for the thud about a week ago. I gave them LI 27.79-P-0556898 and said this should fix it. They performed the service as well as a transmission programming that was not on my service receipt. Thud is gone and gears are shifting smoother than before I went in.
#20
Senior Member
Took the 2014 GLK250 in for the thud about a week ago. I gave them LI 27.79-P-0556898 and said this should fix it. They performed the service as well as a transmission programming that was not on my service receipt. Thud is gone and gears are shifting smoother than before I went in.
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2014 GLK250, 2012 C250 Coupe
Now that a couple more weeks have passed I can say that the thud has been back - but only twice and not as severely as before. Things have definitely improved, but I'm wondering if this will be a service needed every so often in the future...
#22
hello to everyone. I had the same problem and at the mercedes benz service they repalced with a new torque converter, new propeller shaft pump, new oil shaft and other changes and the problem still exists.it happens always after 4-5 secs to a complete stop. Any ideas or solutions? Please
Last edited by vaxhu; 12-09-2018 at 02:58 PM.
#23
I also have the same issue. Mine is 2015GLK250. I have over 70k on my transmission. I called the dealer here at Ontario CA to check it out and they said they will charge me 175 dollars for diagnostic. What I don't understand is why they always charge for diagnostic when I already told them what the problem is. I am not going to this MB dealer/service place anymore.
#24
Had my '14' GLK250 in for a service 'B' today. One of the issues I raised was the thud/clunk a few seconds after coming to a stop. The service writer and I went for a test drive and miracle of miracles. The problem actually presented itself instead of hiding for the test drive. They put in the software update that was mentioned on another thread (three things you don't like about your GLK) about this and other issues. The tech said it still had the issue when he drove it after the update. I didn't notice it on the way home.
Now, The cause of the issue (as explained to me by the tech) is the fact that the MB auto trans has a locking torque converter for better efficiency. Upon stopping for more than a set amount of time at a light. The computer will back off the torque converter completely (almost like a neutral position) while in gear to ease the load on the engine. When the load is released the driveline suddenly 'relaxes'
It's a similar (but much much less) effect as having a manual trans and dragging the clutch a bit and pushing the gear lever into neutral thus causing the drive shaft to ring from the backlash on the ring & pinion gears when torque is suddenly released on the driveline.
Now, The cause of the issue (as explained to me by the tech) is the fact that the MB auto trans has a locking torque converter for better efficiency. Upon stopping for more than a set amount of time at a light. The computer will back off the torque converter completely (almost like a neutral position) while in gear to ease the load on the engine. When the load is released the driveline suddenly 'relaxes'
It's a similar (but much much less) effect as having a manual trans and dragging the clutch a bit and pushing the gear lever into neutral thus causing the drive shaft to ring from the backlash on the ring & pinion gears when torque is suddenly released on the driveline.
#25
This function explain by a mercedes engineer is called “KID” that mean Kraftlos in D, its just a particularity of this automatic shift and its functionality is to reduce power and secure the car when is stopped and ready to start. Till now i had no problems only the terrible thud noise sometimes but now i’m used on it. Most of the mercedes engineers told there is no problem on doing that noise. So don’t worry keep go and enjoy you mercedes
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