So this morning I drove the car as usual and the tire pressure warning turns on, I was like hmm no big deal perhaps there's some nail, just plug it and call it a day (it's very common in my country). Immediately go to tire shop yes indeed the pressure is low (28 psi instead usual 38 psi) and told the mechanic to find the leak.

Well the leak is found, but not because of nail, but its from tire wear :O There is bald spot on 1 spot only. The tire is 1 year old (approx 5000km) and need replacement already?? So I replaced a pair....and did alignment (ouch my wallet) Alignment result only the toe out of spec, they re adjust it. Camber is -2 degree but this cannot be adjusted

The tire shop guy also confused this is first time experience this kind of wear, if out of alignment usually the bald is the whole circumference not only one spot. if the shock breaker is shot, usually the tire has a lot of spot, not only one spot... My suspension components re-checked no sign of failure (I replaced almost all suspension components a year ago). The coilover also one year old and still good (at least for me) no bouncy/floaty ride.



Perhaps photos hard to see, but here's the video I hope its clear enough.

What possibly caused this? (I don't want to replace tire every year :O ) My other car usually I replace every 5 year, not because reached TWI but due to its age

 

Hi, I'm not sure if you've checked, but if the wheels aren't the original ones, and if the ET and J (width) of the wheels don't match the vehicle, the tire might come into contact with the spring housing and the shock absorber. I had the same problem this summer, but in my case, it was due to the alignment. After I had it adjusted, there were no more issues.

 

camber out of whack.
Did they check alignment?
Happened to me no adjustment from factory unless you buy some special bolts which give you fixed camber adjustment of I think1/2 degree either way for front.

For rears not sure factory has fix but aftermarket does, - Google on here camber adjustment and you get either adjustable camber arms or eccentric adjustable bushing kit.

 

Mas Tesna,

The tire in the photo, from which side of the car is that ?
The right side the worn out one is the INNER side right ?

Show me from google link, which version is your BC Racing Coilover as installed at the moment.

01. That kind of worn out can only happen from scrubbing something.

02. Show me your alignment report. Rear Camber at -2 degrees is too much for non AMG W212.

 

Inside edge worn is either camber or the toe is too open. There is no adjustment from factory for camber but there is for toe.

 

yeah the possible explanation is hitting the suspension tower/spring housing, perhaps when under load. But there was no sign of scrubbing (perhaps already happened a while ago?) the alignment shop also checked the clearance is good.

yes, alignment are re-checked and reajusted.

it's the front left, and yes its the inside that wears. Yes that what also the alignment mechanic says to me, its scrubbing something but scrubbing what.... some road debris?

my coilover is https://bcracing.com.au/products/bc-...212-10-current

I always wondered why the front spring rate is much lower than the one in the back, I thought the engine being at the front should have higher springs rate. I'm planning back to re install my bilstein b4 + lowering spring (but not the h&r as that one has aggresive drop, lower than my current coilover setup height)



attached is the alignment report, the toe was out of spec but now re adjusted. The camber being -2 I thought being normal for lowered car than standard.

yes the toe was out of spec and now has been re adjusted, the alignment report is attached in this post

 

Can you check the front strut mounting style to the wheel knuckle assy.
I think the website below is showing a wrong type or generic type just for photo sake.
https://bcracing.com.tw/result?nowca...owchassisnote=



The right image is Bilstein B4



What is your rim full spec ? Its ET/offset too.

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This is standard SACHS damper front wheel clearance, with original AMG wheel ET48, 8.5J, 18".


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@S-Prihadi here's photo from underneath, quite similar to stock. However the lower spring mount is much smaller and gives more room than stock shocks.



The rim spec 19x8.5 ET 45 (I added 11mm spacer "nok" so making its ET to 35 front, and rear 19x9.5 ET 45 (without spacer)

 

Your suspension IF STANDARD is a 485 Comfort.

The current front Camber is so bad at -2 degree 44 minutes for left front and -2*07 for right front. This is much likely from lowering and a bit from the 10mm spacer.
ADD: Worn out bushing on suspension arm can also do this.
Your front tires even say without this weird very localized inner wear of front left tire, both sides will experience accelerated inner side wear nevertheless.
This camber setting at straight line high speed or daily driving is not good, but at high G corners it has benefit.
The 10mm spacer will upset the scrub radius, aside from the lowering.


How is the Right front tire wear ?

485 suspension front camber spec is 0 degree 23' minutes ( +-21' minutes ) at its designed ride height, a +2.56 degree Romess at the arm.


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The Left rear is also out of spec too at 2 degree 1 minutes.



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TOE- FRONT



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TOE - Rear



So the front toe was initially very bad for Left Front at zero degree 21 minutes. Later corrected to zero degree 3 minutes.
The right front was minus zero degree 5 minutes.Later corrected to zero degree 3 minutes.
These are very out of whack numbers.

The front toe, the techy was following their machine database at total of positive 5 minutes, hence total toe is positive 6 minutes and not positive 9 minutes.

The rear toe was decent but could have been improved, but it was probably untouched. Probably the shop does not have the Torx T55.
It should have been set to positive 11 minutes each side to be at the nice middle spec, of positive 21 minutes total toe +- 7 minutes.

Notice how these alignment machine database ( SPECIFIED RANGE ) is all wrong... . It is a mix of AMG, 485, 486. 677 database.
That is why you need to bring your own alignment specs.

Even newer Hunter alignment machine sold by their local dealer, the database for Mercedes is poor. I wonder who manages all these database ?
Very few owners would know their suspension type , unless they study their data card. This makes everything worse.

Mercedes cars are probably one of the complex one, for their suspension variants due to so many types of suspension code and RWD or 4-Matic.

 

@S-Prihadi the right front tire still OK no sign of excessive wear, but I replaced it anyway since I changed brand tire and it needs to be replaced at least a pair, right.

I thought camber -3 is quite acceptable, my previous car also lowered and have similar camber figure (too lazy to get a camber kit) but the tires does last 50k kms, which is acceptable for me as 5 year old tire considered not fit to use anymore. But 1 year is not acceptable. I can accept if the wear is whole inner and the whole circle, but such a weird spot make me worried.

As the correct toe specs, Should I bring back to the shop to readjust the toe? I still have 14 day warranty to complain.

 

W212 excellent high speed straight line stability when all suspension components are healthy , and best if Bilstein B4 all around or B6 at the rear for those who wants better handling, is from a proper alignment value set
by MB.

When I said straight line stability is not flat smooth tarmac, but the poor road to bridge joints found on our national paid highway and some un-even road at the super bad Cikopo-Palimanan-Kanci-Pamalang
or up to 400KM ( Semarang ) from Jakarta to Surabaya paid highway. The 450-600 KM is very good .

Usually after bumps or jumps, car may wonder off a bit, but W212 is excellent at this department.

Also standard car front Camber rarely ever we will find higher than -1 degree, as 99% time spent on daily car is not at high G corners, but wider corner if not straight line.

Try running say 180KM/H and do maximum hard braking down to 50KM/H, if your camber is that high, you wont get a nice easy hands free braking, your car front wont be too "friendly".


FWD cars, daily use, some people like to add more camber. Example CIVIC-R 10th gen from factory has high negative camber due to its intended sport use and a FWD drive train :




Civic R 10th Gen 2015 to 2022 , 315 HP Front Wheel Drive


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If your alignment shop is nice enough to use the correct Toe value for front and rear, go ahead and get it done for the rear. Front is very OK.
Note 110Nm torque when rear toe done. Call them ahead and ask if they have the Torx T55,




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T55 Torx


W212 has large workroom to even use T55 on a ratcheting wrench.



W204 2010, shorter car, the toe arm is hidden under the plastic shield and very close to fuel tank. Can only use L shaped T55.
I cut a service hole for my friend C200 W204. under-shield.



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well, since the wear is not all the way around, I would say this is a bad tire made incorrectly, although your alignment wasn't perfect, it was not out enough nor was it a contributing factor here IMHO

 

I finally installed camber kit, finally its now within specs....


hardrace arm assembly

mb correction bolt

rear installed

after front correction bolt installed it only improve by 0.3 degree, the mechanic at alignment shop found that the bolt hole is oval shaped so camber adjustment is possible

After alignment/camber correction the car seems sitting higher than before, I hope no more premature tire wear after this...