Tyre scrubbing on (full) lock
#651
Newbie
Join Date: Feb 2017
Posts: 9
Likes: 0
Received 1 Like
on
1 Post
GLC Coupe, 250d AMG Line, Premium Plus, Night Pack.
Avoid all the hassle and stop being ripped of by MB and do what I did, I part exchanged my GLC AMG Line Coupe Premium Plus with crabbing at a good price compared to the discounted purchase price for the new Audi SQ5 which has driven faultlessly for the year I've owned it, as far as I'm concerned MB suck for ripping us off and they won't do it to me again. I'm impressed so many stayed with their hop skipping GLCs with annual tyre changes, MB must love you all......
Last edited by RickZ; 12-02-2018 at 04:04 AM.
#652
MBWorld Fanatic!
Join Date: Mar 2016
Location: Melbourne, Australia
Posts: 1,030
Received 155 Likes
on
128 Posts
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
Stop the Presses !!
This is from our UK sister site....
“ Just had a very interesting telephone call with mercedes customer help about tyre replacement for the crabbing complaints on glc models.They have said that when my car gets delivered next week if i have a problem with tyre crabbing that they would replace the tyres with all season tyres but also as of yesterday they have engineered a different suspension knuckle that helps alleviate the crabbing problem and it would more than likely be that this would be there first action that they would do.Hope this is true and it helps anyone who is having this issue.
unfortunately mine was built before this rectification was done at build stage. “
“ I was contacted by Mercedes UK yesterday they say they have identified an engineering solution to the problem and, will retrofit the new parts in January, FOC under the 3 year warranty. A little bird tells me that they won't recall every vehicle they will only do those where there has been a complaint. “
Maybe something along the way to a solution, may not eradicate, but may help with tension and alignment settings........
This is worth making more enquiring with MB Oz and Dealers, my guess is feedback may not happen until Feb 19 here at the earliest, given UK are RHD like ours........
This is from our UK sister site....
“ Just had a very interesting telephone call with mercedes customer help about tyre replacement for the crabbing complaints on glc models.They have said that when my car gets delivered next week if i have a problem with tyre crabbing that they would replace the tyres with all season tyres but also as of yesterday they have engineered a different suspension knuckle that helps alleviate the crabbing problem and it would more than likely be that this would be there first action that they would do.Hope this is true and it helps anyone who is having this issue.
unfortunately mine was built before this rectification was done at build stage. “
“ I was contacted by Mercedes UK yesterday they say they have identified an engineering solution to the problem and, will retrofit the new parts in January, FOC under the 3 year warranty. A little bird tells me that they won't recall every vehicle they will only do those where there has been a complaint. “
Maybe something along the way to a solution, may not eradicate, but may help with tension and alignment settings........
This is worth making more enquiring with MB Oz and Dealers, my guess is feedback may not happen until Feb 19 here at the earliest, given UK are RHD like ours........
#653
MBWorld Fanatic!
Stop the Presses !!
This is from our UK sister site....
“ Just had a very interesting telephone call with mercedes customer help about tyre replacement for the crabbing complaints on glc models.They have said that when my car gets delivered next week if i have a problem with tyre crabbing that they would replace the tyres with all season tyres but also as of yesterday they have engineered a different suspension knuckle that helps alleviate the crabbing problem and it would more than likely be that this would be there first action that they would do.Hope this is true and it helps anyone who is having this issue.
unfortunately mine was built before this rectification was done at build stage. “
“ I was contacted by Mercedes UK yesterday they say they have identified an engineering solution to the problem and, will retrofit the new parts in January, FOC under the 3 year warranty. A little bird tells me that they won't recall every vehicle they will only do those where there has been a complaint. “
Maybe something along the way to a solution, may not eradicate, but may help with tension and alignment settings........
This is worth making more enquiring with MB Oz and Dealers, my guess is feedback may not happen until Feb 19 here at the earliest, given UK are RHD like ours........
This is from our UK sister site....
“ Just had a very interesting telephone call with mercedes customer help about tyre replacement for the crabbing complaints on glc models.They have said that when my car gets delivered next week if i have a problem with tyre crabbing that they would replace the tyres with all season tyres but also as of yesterday they have engineered a different suspension knuckle that helps alleviate the crabbing problem and it would more than likely be that this would be there first action that they would do.Hope this is true and it helps anyone who is having this issue.
unfortunately mine was built before this rectification was done at build stage. “
“ I was contacted by Mercedes UK yesterday they say they have identified an engineering solution to the problem and, will retrofit the new parts in January, FOC under the 3 year warranty. A little bird tells me that they won't recall every vehicle they will only do those where there has been a complaint. “
Maybe something along the way to a solution, may not eradicate, but may help with tension and alignment settings........
This is worth making more enquiring with MB Oz and Dealers, my guess is feedback may not happen until Feb 19 here at the earliest, given UK are RHD like ours........
#654
I'd like to bring up a possible cause that I have not seen discussed in other posts. I have spent the last couple hours reading all the posts in the various forums regarding the GLC scrubbing and judder problem. I’ve watched (and listened to) the videos and looked at the photos that have been posted, and I fully appreciate why owners are dissatisfied. At about 1:06 in dejongj’s recent video, you can see the tire suddenly slip sideways and then regain traction.
The center differential in the GLC (and many other modern MB 4matic models) has a multiple-disc clutch with a "basic locking force of 37 foot-pounds (50 newton-meters)." (Quote from the original GLC press release.) The center differential in the GLC does not employ electronics or hydraulics to lock or unlock. It is strictly a mechanical device with a breakaway clutch. I would call it a limited-lock differential.
The breakaway clutch causes the front and rear driveshafts to be locked together -- turning at exactly the same speed -- until sufficient torque is exerted to cause the breakaway clutch to slip. Until that clutch slips, the drivetrain behaves like an old-fashion 4x4 with no center differential. When the front axle is trying to turn at a different speed from the back axle, torque is exerted on the breakaway clutch in the center differential. How much torque? Well, that depends on how much grip there is between the tires and the pavement (or ice or snow or whatever the tires are touching).
If you've ever used a torque wrench, you know that 37 foot-pounds isn't much torque. But the GLC43 has a 3.69:1 final drive ratio, so that's 137 ft-lbs of torque at the wheels. Can a GLC43 with cool 21” “summer” tires turned to full-lock on wet pavement generate that much torque? My intuition says yes, but I’m really just guessing.
What would happen at low speeds if the tires didn’t have enough grip to cause the breakaway clutch to slip? Well, pretty much everything that GLC owners have been describing in the forums I’ve seen. The vehicle would act like an old-fashion 4x4 with no center diff (or a locked center diff). At low speeds with the steering wheel turned sharply, the front tires would scrub and jerk and the vehicle would understeer (ie, act like it doesn’t want to turn). As the tires alternated between slipping and gripping, the drivetrain would alternate between slack and taught, and various unpleasant drivetrain noises would ensue.
Could the size or type of tire make this problem better or worse? If the vehicle consistently has enough tire grip to overcome the “basic locking force” of the breakaway clutch, then the symptoms would go away. The rubber compounds in the treads of winter tires are soft and grippy, even when cold. So winter tires would probably improve – or eliminate – the low speed, full-lock scrubbing symptoms.
I am very skeptical that there is a design flaw in the steering geometry. And I’m fairly skeptical that this is an alignment issue. I am puzzled that this seems to be limited to RHD models. But the symptoms make me suspicious of the breakaway clutch. Specifically, I wonder whether there was a manufacturing problem that caused some (but not all) clutches to have a breakaway torque of more than 37 ft-lbs. Lots of things could cause this: thickness of the clutch plates was out of spec, a change to the compound or supplier of the clutch discs, a change to the specs or supplier of the lubricant in the differential, etc, etc. (Many moons ago, I was a warranty engineer at the Honda factory in Ohio, USA. I’ve seen a few things.)
For what it’s worth, I took my wife’s GLC43 (with 19” Pirelli snow tires) out today and could not duplicate the symptoms that others are experiencing. It was 15*F. Roads were either dry or had a thin layer of packed snow. The next time it rains, I will try again on wet roads.
The center differential in the GLC (and many other modern MB 4matic models) has a multiple-disc clutch with a "basic locking force of 37 foot-pounds (50 newton-meters)." (Quote from the original GLC press release.) The center differential in the GLC does not employ electronics or hydraulics to lock or unlock. It is strictly a mechanical device with a breakaway clutch. I would call it a limited-lock differential.
The breakaway clutch causes the front and rear driveshafts to be locked together -- turning at exactly the same speed -- until sufficient torque is exerted to cause the breakaway clutch to slip. Until that clutch slips, the drivetrain behaves like an old-fashion 4x4 with no center differential. When the front axle is trying to turn at a different speed from the back axle, torque is exerted on the breakaway clutch in the center differential. How much torque? Well, that depends on how much grip there is between the tires and the pavement (or ice or snow or whatever the tires are touching).
If you've ever used a torque wrench, you know that 37 foot-pounds isn't much torque. But the GLC43 has a 3.69:1 final drive ratio, so that's 137 ft-lbs of torque at the wheels. Can a GLC43 with cool 21” “summer” tires turned to full-lock on wet pavement generate that much torque? My intuition says yes, but I’m really just guessing.
What would happen at low speeds if the tires didn’t have enough grip to cause the breakaway clutch to slip? Well, pretty much everything that GLC owners have been describing in the forums I’ve seen. The vehicle would act like an old-fashion 4x4 with no center diff (or a locked center diff). At low speeds with the steering wheel turned sharply, the front tires would scrub and jerk and the vehicle would understeer (ie, act like it doesn’t want to turn). As the tires alternated between slipping and gripping, the drivetrain would alternate between slack and taught, and various unpleasant drivetrain noises would ensue.
Could the size or type of tire make this problem better or worse? If the vehicle consistently has enough tire grip to overcome the “basic locking force” of the breakaway clutch, then the symptoms would go away. The rubber compounds in the treads of winter tires are soft and grippy, even when cold. So winter tires would probably improve – or eliminate – the low speed, full-lock scrubbing symptoms.
I am very skeptical that there is a design flaw in the steering geometry. And I’m fairly skeptical that this is an alignment issue. I am puzzled that this seems to be limited to RHD models. But the symptoms make me suspicious of the breakaway clutch. Specifically, I wonder whether there was a manufacturing problem that caused some (but not all) clutches to have a breakaway torque of more than 37 ft-lbs. Lots of things could cause this: thickness of the clutch plates was out of spec, a change to the compound or supplier of the clutch discs, a change to the specs or supplier of the lubricant in the differential, etc, etc. (Many moons ago, I was a warranty engineer at the Honda factory in Ohio, USA. I’ve seen a few things.)
For what it’s worth, I took my wife’s GLC43 (with 19” Pirelli snow tires) out today and could not duplicate the symptoms that others are experiencing. It was 15*F. Roads were either dry or had a thin layer of packed snow. The next time it rains, I will try again on wet roads.
Hi,
Mine is RHD and I tried to slowly roll the car without engine load (at neutral) and at full steering lock whilst the crabbing noise is still there so I think that must come from the alignment of RHD model
#655
GLC Crabbing Fixed!
After 2 years of ownership and complaining about the well reported crabbing / scrubbing issue, my dealership contacted me to say that a fix has been released by the factory. They duly fitted, what they referred to as, replacement steering knuckle joints. The weather has warmed up a little, but so far, no more juddering on full lock in forward or reverse; fingers crossed!
#656
MBWorld Fanatic!
After 2 years of ownership and complaining about the well reported crabbing / scrubbing issue, my dealership contacted me to say that a fix has been released by the factory. They duly fitted, what they referred to as, replacement steering knuckle joints. The weather has warmed up a little, but so far, no more juddering on full lock in forward or reverse; fingers crossed!
#657
Junior Member
After 2 years of ownership and complaining about the well reported crabbing / scrubbing issue, my dealership contacted me to say that a fix has been released by the factory. They duly fitted, what they referred to as, replacement steering knuckle joints. The weather has warmed up a little, but so far, no more juddering on full lock in forward or reverse; fingers crossed!
MA253-332-33-00 and MA253-332-34-00
There is a thread running on the subject over on the more UK-centred GLC Forums:
Click here: Steering Knuckle Anti-clonking Fix
#658
Junior Member
![Thumbs up](https://mbworld.org/forums/images/icons/icon14.gif)
If any Right Hand Drive, non-43/63 owners would like to see photos of the modified steering knuckle Mercedes have designed to correct the tyre skipping characteristic, I have uploaded some in this particular post over on the GLC Forums:
Steering Knuckle Anti-Clonking Fix
Steering Knuckle Anti-Clonking Fix
Last edited by Toobad; 04-11-2019 at 12:12 PM.
The following users liked this post:
Teckno (04-12-2019)
#659
MBWorld Fanatic!
Join Date: Mar 2016
Location: Melbourne, Australia
Posts: 1,030
Received 155 Likes
on
128 Posts
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
Great News.......
Well it looks like the flood gates have been opened in Oz for the knuckle replacement program to RHD vehicles.
Our 250d, with air suspension finally was approved last week and car was converted.
Limited driving to date, but it seems what we thought it should be like on wet and cold roads doing is actually finally happening.
Our tyres are Goodyear All Season, run flats.
Can posters who have the conversion done please let us know if their tyres are All Season type, or original Summer runflats, by brand.
If a Coupe, were tyres changed or are they original non run flats ? Brand ?
Thanks to everyone for sharing info.
Well it looks like the flood gates have been opened in Oz for the knuckle replacement program to RHD vehicles.
Our 250d, with air suspension finally was approved last week and car was converted.
Limited driving to date, but it seems what we thought it should be like on wet and cold roads doing is actually finally happening.
Our tyres are Goodyear All Season, run flats.
Can posters who have the conversion done please let us know if their tyres are All Season type, or original Summer runflats, by brand.
If a Coupe, were tyres changed or are they original non run flats ? Brand ?
Thanks to everyone for sharing info.
#660
Member
Great News.......
Well it looks like the flood gates have been opened in Oz for the knuckle replacement program to RHD vehicles.
Our 250d, with air suspension finally was approved last week and car was converted.
Limited driving to date, but it seems what we thought it should be like on wet and cold roads doing is actually finally happening.
Our tyres are Goodyear All Season, run flats.
Can posters who have the conversion done please let us know if their tyres are All Season type, or original Summer runflats, by brand.
If a Coupe, were tyres changed or are they original non run flats ? Brand ?
Thanks to everyone for sharing info.
Well it looks like the flood gates have been opened in Oz for the knuckle replacement program to RHD vehicles.
Our 250d, with air suspension finally was approved last week and car was converted.
Limited driving to date, but it seems what we thought it should be like on wet and cold roads doing is actually finally happening.
Our tyres are Goodyear All Season, run flats.
Can posters who have the conversion done please let us know if their tyres are All Season type, or original Summer runflats, by brand.
If a Coupe, were tyres changed or are they original non run flats ? Brand ?
Thanks to everyone for sharing info.
Great news!
#661
MBWorld Fanatic!
Join Date: Mar 2016
Location: Melbourne, Australia
Posts: 1,030
Received 155 Likes
on
128 Posts
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
That said, contact Mulgrave, raise a personal ‘claim’ and have them confirm. It may also serve as a bookmark if a solution is identified, after your warranty period expires, that way ‘Goodwill’ will come into play.
I have not heard why these two models are excluded, maybe final drive ratios between front and rear AWD percentages. Or it could be torque ratios and stress capacity ?
Given the large numbers of 43’s in Oz, Mulgrave may be working on this ?
#662
MBWorld Fanatic!
From my Enquiries and info coming out of UK, this fix applies to Non 43 and Non 63. Only 200, 220 and 250 in petrol and diesel.
That said, contact Mulgrave, raise a personal ‘claim’ and have them confirm. It may also serve as a bookmark if a solution is identified, after your warranty period expires, that way ‘Goodwill’ will come into play.
I have not heard why these two models are excluded, maybe final drive ratios between front and rear AWD percentages. Or it could be torque ratios and stress capacity ?
Given the large numbers of 43’s in Oz, Mulgrave may be working on this ?
That said, contact Mulgrave, raise a personal ‘claim’ and have them confirm. It may also serve as a bookmark if a solution is identified, after your warranty period expires, that way ‘Goodwill’ will come into play.
I have not heard why these two models are excluded, maybe final drive ratios between front and rear AWD percentages. Or it could be torque ratios and stress capacity ?
Given the large numbers of 43’s in Oz, Mulgrave may be working on this ?
The following users liked this post:
Teckno (06-21-2019)
#663
MBWorld Fanatic!
Join Date: Mar 2016
Location: Melbourne, Australia
Posts: 1,030
Received 155 Likes
on
128 Posts
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
Re claiming assistance for knuckle fix for your GLC. In Australia.
A number of dealers will actually know nothing as regards the conversion. I do not think MBAu have sent out any Warning Bulletin.
my dealer had not done one until we fronted and they sent off a report to Mulgrave, who approved work 2 hours later.
My recommendation is to go to Mulgrave HQ site and go to the Contact Us portal.
A number of dealers will actually know nothing as regards the conversion. I do not think MBAu have sent out any Warning Bulletin.
my dealer had not done one until we fronted and they sent off a report to Mulgrave, who approved work 2 hours later.
My recommendation is to go to Mulgrave HQ site and go to the Contact Us portal.
Fill out your personal details and state which dealer you want them to contact. Ask for inspection and supply of parts for free conversion. No need to quote part numbers.
Keep it simple – ask for the knuckle replacement fix.
They should contact you and say they have sent your email to the relevant Division, in HQ, who will contact you within 48 hours.
If nothing heard 3 days later use email address they used to send back a ‘what’s the delay’ email – that should get a response.
Concurrently I would contact your dealer and book the car in for inspection a week after you send your email – that way you can let Mulgrave know when it is booked in when they contact you, this will help fast track – hopefully they have enough spares in the system.
Hope this helps readers who want their cars fixed.
At this stage I do not believe there is a fix for GLC350d, GLC43 or GLC63 variants.
That said, if you own one, I would still contact Mulgrave to ‘register’ your concerns and request you be listed for assistance when a mechanical solution is identified and provided to owners, even if car out of 3 year warranty – other warranty conditions may ‘kick in’ as per ACCC rules, based on cost of car and reasonable ‘expectations’ – given precedent of GLC fix to date.
Good luck.
Last edited by Teckno; 06-23-2019 at 10:58 AM. Reason: Address
The following users liked this post:
tiger_x (06-25-2019)
#665
MBWorld Fanatic!
Join Date: Mar 2016
Location: Melbourne, Australia
Posts: 1,030
Received 155 Likes
on
128 Posts
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
Found this on line post and link.
Fisher writes...
the tyre skipping is less frequent or less annoying when the car was brand new, very likely the tyre was new. As the tyre starts to running down, it gradually becomes more unpleasant noticeable
Hmm is it about this petition?
https://www.change.org/p/mercedes-be...des-benz-c-glc
Fisher writes...
the tyre skipping is less frequent or less annoying when the car was brand new, very likely the tyre was new. As the tyre starts to running down, it gradually becomes more unpleasant noticeable
Hmm is it about this petition?
https://www.change.org/p/mercedes-be...des-benz-c-glc
#666
Junior Member
Copy of my post on Australian Whirpool forum. https://whrl.pl/RfoAyb
Knuckle replacement completed.
First impressions:
Any evidence of wheel crabbing/scrubbing ….gone.
Understeer at near full lock turn on wet surface (small round-a-bout) …..Gone.
Tyre wear? ...give me 10,000 km, though not sure I have 10K left in the Bridgestones.
Generally feels a bit better in corners, slight increase in centering force of steering. (this had decreased after wheel alignment done prior to knuckle change) ..Handling feel in corners, subtle, but feels better.
Any GLC owner ...just do it!!
Knuckle replacement completed.
First impressions:
Any evidence of wheel crabbing/scrubbing ….gone.
Understeer at near full lock turn on wet surface (small round-a-bout) …..Gone.
Tyre wear? ...give me 10,000 km, though not sure I have 10K left in the Bridgestones.
Generally feels a bit better in corners, slight increase in centering force of steering. (this had decreased after wheel alignment done prior to knuckle change) ..Handling feel in corners, subtle, but feels better.
Any GLC owner ...just do it!!
Last edited by Citizen613; 07-06-2019 at 08:39 PM.
#667
MBWorld Fanatic!
Join Date: Mar 2016
Location: Melbourne, Australia
Posts: 1,030
Received 155 Likes
on
128 Posts
2016 GLC 250d AMG pack, 2017 GLC Coupe 250d AMG pack , 2002 BMW 330Ci convertible, 2021 BMX X1 sD20i
Info from Australian site.
@65289679 Yokat writes...
["In ordering the new 2020 GLC 63s Coupe, raised the crabbing issue and the salesman investigated with MB Australia and came back with the advice "apparently the tyre skip issue has been fixed in the 63". Here's hoping as I have placed an order. Currently have the 43 and a change in front tyres successfully masked the issue and the car is great, hoping the 63s experience is smooth
"]
I seriously doubt this is fact, I hope I am proved wrong. UK, RHD GLC market has no info re this and based on past experience with tyre developments and knuckle testing, I would have thought UK would know before Oz. Maybe a production line fix, but that fix should be backwards compatible???????
Buyer has been advised to get this new advice’ in writing’.
Time will tell.
@65289679 Yokat writes...
["In ordering the new 2020 GLC 63s Coupe, raised the crabbing issue and the salesman investigated with MB Australia and came back with the advice "apparently the tyre skip issue has been fixed in the 63". Here's hoping as I have placed an order. Currently have the 43 and a change in front tyres successfully masked the issue and the car is great, hoping the 63s experience is smooth
![Big Grin](https://mbworld.org/forums/images/smilies/biggrin.gif)
I seriously doubt this is fact, I hope I am proved wrong. UK, RHD GLC market has no info re this and based on past experience with tyre developments and knuckle testing, I would have thought UK would know before Oz. Maybe a production line fix, but that fix should be backwards compatible???????
Buyer has been advised to get this new advice’ in writing’.
Time will tell.
#668
Newbie
Join Date: Jun 2013
Location: Melbourne
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
E63s, C63 507
Front Tyres scrubbing on full-lock
Hi
the front tyres my 2019 E63s scrub when on full-lock. Now with 30,000ks the inside of both front tyres has worn to the canvas yet the main part of the tread is OK. Could it be too much castor? Has anyone found a solution for this issue?
Jim
the front tyres my 2019 E63s scrub when on full-lock. Now with 30,000ks the inside of both front tyres has worn to the canvas yet the main part of the tread is OK. Could it be too much castor? Has anyone found a solution for this issue?
Jim