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Long post, but will start from the beginning. About 3 weeks ago I started driving home from work and noticed the tire pressure monitor light up, saying that the right rear tire is too low. Filled it up at the gas station and decided to wait and see what it will do the next day. In the morning it lighted up again and I took the car to a nearby tire shop. My first though was that it had a screw in there. The guys at the shop took a look at it and said that my tire is worn to the cord (picture attached). Well ****... I knew I needed to replace them, but didn't know it was that bad (kinda my fault for not checking them that often, but the rest of the tire looked good). Anyway, since I didn't have any new tires laying around I asked them to fill it up and ordered new fresh set of 275/30/19 Michelin Pilot Sport 4S. Managed to drive the car for around 5 days when the rear tire blew on my way home. Had the car towed to the shop and just waited for the new tires to arrive. Fast forward a week and I had the new tires installed. Meanwhile I also did some searching around the forum and found many of you with bad inner tire wear, so I booked an alignment at the dealer. Well, let's say the answer I got from them didn't make me happy. All 4 wheels were out of spec and they managed to align 3. The right rear camber was quite a bit out of alignment, but since our camber is not adjustable on our cars then there wasn't anything they could do about it. I only asked them to use the lowest toe-in setting (that's what many of you also suggest around here). When asking what was wrong with the camber they were quite short in their answer - they didn't know. The best guess the alignment guy said was that probably my right rear control arm is bent or deformed in somehow making the rear right tire eat itself. Since I don't want this to happen to my new tires I asked them to order new parts (500 euros for work and labour). Now I have to wait another week until the parts arrives and they can replace it.
So, just wondering - anyone had any similar problems like this? It kinda sucks that the dealer couldn't figure out if it is control arm or not. Fingers crossed it is... I also attached 2 pictures how the back of the car looks. You can clearly see that the right rear wheel has much bigger negative camber that the right one.
Is your car lowered ? I have the kmac rear kit and it has worked well for the time I've had it installed (10k miles)
I had a set of arms similar to those on my w203 and they worked fine as well although some other members ran into some problems if I remember correctly with some of them not maintaining set length and others having the bushings bind up and or fail
Last edited by deadlyvt; Oct 10, 2017 at 02:26 PM.
No, not lowered (as far as I am aware). The difference seems to be that the K-Mac is only bushing but my Ebay link is full arms with bushings attached. I already paid 566 dollars to the dealer for new control arms what didn't change jack **** so I'd rather order something cheaper what will give me the same result
No, not lowered (as far as I am aware). The difference seems to be that the K-Mac is only bushing but my Ebay link is full arms with bushings attached. I already paid 566 dollars to the dealer for new control arms what didn't change jack **** so I'd rather order something cheaper what will give me the same result
We do not manufacture the “rear arms”.
Instead replacement inner bushings for the lower control arms. This allows to adjust base of wheels inwards to resolve costly/premature inner edge tire wear.
While the rear arms adjust top of tire outwards reducing important clearance to outer fender and are difficult to access and adjust.
The K-MAC bushes have twice the load bearing area and are precisely singe wrench adjustable on car, accurately (under load) direct on alignment rack. Bush extraction tool is included.
OP, aren't you concerned from a different perspective as well: the new arm did not correct the problem.That implies strongly does it not that something in the chassis is bent (i.e. the wheel is tilted because the MOUNT points for the arm are no longer where they are supposed to be). Did you hit a pavement pothole particularly hard?
OP, aren't you concerned from a different perspective as well: the new arm did not correct the problem.That implies strongly does it not that something in the chassis is bent (i.e. the wheel is tilted because the MOUNT points for the arm are no longer where they are supposed to be). Did you hit a pavement pothole particularly hard?
Seen more bent knuckles than anything else. If both tires are getting chewed up you can raise the vehicle level or get the K-mac bushings. Recently put a set on a car and they provide a good amount of adjustment. Overtime you take off hard and the rear end squats down you will have negative camber as well. I would be more upset with the people that sold you the arms. If only the RR was out of spec you could spend the time to make some measurements rather than just guessing.
Do you know how far out of spec it is?
If your lower control arm was bent it would effectively make the arm shorter. A shorter lower control arm will put the camber to the positive side and not negative. I would be doing a thorough inspection comparing measurements side to side of everything. When the knuckle gets bent you can typically see slight differences in distance of the arm mounting points to the backing plate or brake rotor. check all mounting points. usually upper ones bend out which brings the top side in more.
Last edited by knowbenz; Oct 12, 2017 at 01:19 AM.
I really can't remember hitting a pothole or anything. Sadly I haven't noticed the negative camber before and it already might have been out of alignment when I got my car in April. I do drive the car had and give it the full beans quite often, but hey - who doesn't? The dealer named me another part what they recommended me to change (I really don't remember the name, somewhere behind the breaks - could have been the knuckle?) but the cost of the part alone was 1100 dollars. They also said that they can't find anything in particular wrong with chassis, so hunting down the root cause of this issue might get very expensive. That's why I'm now looking at new adjustable control arms and dealer also confirmed that it's very likely to get the negative camber fixed with it. I also contacted another indie shop and they said that they had a customer with SL63 AMG with the same inner tire wear issue and the camber kit fixed it. If I remember correctly then the RR camber is -1 degree out of spec of the recommended value.
I really can't remember hitting a pothole or anything. Sadly I haven't noticed the negative camber before and it already might have been out of alignment when I got my car in April. I do drive the car had and give it the full beans quite often, but hey - who doesn't? The dealer named me another part what they recommended me to change (I really don't remember the name, somewhere behind the breaks - could have been the knuckle?) but the cost of the part alone was 1100 dollars. They also said that they can't find anything in particular wrong with chassis, so hunting down the root cause of this issue might get very expensive. That's why I'm now looking at new adjustable control arms and dealer also confirmed that it's very likely to get the negative camber fixed with it. I also contacted another indie shop and they said that they had a customer with SL63 AMG with the same inner tire wear issue and the camber kit fixed it. If I remember correctly then the RR camber is -1 degree out of spec of the recommended value.
Looking at the pictures again it is clear that it is out of spec. Like you said, the camber isn't adjustable so something is bent. I personally wouldn't be going to a dealer that can't be confident in their diagnosis. That price seems right for a knuckle from the dealer. Find a good independent shop that has experience with alignment diagnosis. If you want to save some money you can get a salvaged knuckle for much much cheaper. If you have something bent it would be much wiser to address that problem instead of covering it up with a camber kit. Whatever is bent could also be weaker from whatever incident caused it. What part of the world are you in?
I'm from northern Europe - Estonia to be precise. Yes, hunting down the root of this issue seems like the reasonable and adult thing to do, but since our cars have aggressive rear camber anyway I would probably still need to order some kind of camber kit to address that issue, because even if it is the knuckle the camber needs to be aligned anyway... So it would be the knuckle + camber kit + labour. I sent a quite spicy letter to my dealer and I'll see what they will answer me tomorrow since my car is still under warranty and I'd rather let them work on it.
I'm from northern Europe - Estonia to be precise. Yes, hunting down the root of this issue seems like the reasonable and adult thing to do, but since our cars have aggressive rear camber anyway I would probably still need to order some kind of camber kit to address that issue, because even if it is the knuckle the camber needs to be aligned anyway... So it would be the knuckle + camber kit + labour. I sent a quite spicy letter to my dealer and I'll see what they will answer me tomorrow since my car is still under warranty and I'd rather let them work on it.
I ended up ordering the eBay camber kit, I know forum member AMG3.2 is also using them and it seems to be working for him. I'll report back when I have them installed (hopefully dealer will give me some good discount, because they already made me pay them for parts and labour what didn't fix anything).
Update. Got the car back with the eBay camber kit is installed. The dealer said the installation wasn't as easy as the kit seemed to show, but never the less they got it installed and also confirmed that the camber issue is now fixed. I also attached a copy of the alignment sheet. Toe seems to be fine - I asked them to use the smallest spec. Now when looking at the camber I still see that it is quite aggressive and when looking the car from the rear I can see it sitting wheels out (looks mean though). Unfortunately I'm quite sure if I'm going to keep this spec the rears will wear out in no time. So, could I get some feedback and comments on the camber the car currently has? I think it's still way too negative and needs to be dialed out to be more positive. What camber are you guys running on?
Not sure if I am reading it right but did they add more camber to it ? And the camber from one side to the other is almost half a degree different ?
I run 1 degree in the rear for street and have reduced the overall toe from factory to help save the rear tires and enjoy the setup on the street
Don't look at the before numbers because those are messed because of the newly installed camber kit, but yeah, I can see they increased the negative camber. Proprably because the dealer is only adjusting it according to the official specifications what Mercedes reccomends, which is way to aggressive. Also, don't let the right rear camber scare you because -2°01' (read it as -1°61') is only 6' away from the minimum -1°55' spec, so well within the 30' scale and the left rear is 10', so in the spec as well.
I looks like the before numbers on camber were actually on the money for one wheel and out on the other, now it is out on both.
If the wheel is at 1 50 and spec is 1 46 why would they adjust it to 2 01?
Toe looks great but they made your camber worse.
My guess is that the still-undiagnosed underlying problem (discussed earlier in the thread) has not been resolved, and the technician was therefore unable to get the "bent" wheel into better spec, and did not want the 2 wheels to be notably different, so set them both to as close to spec as the bent situation would allow. Just a guess, but if you were the technician, what would YOU do if the customer had not authorized a chassis integrity measurement?
My guess is that the still-undiagnosed underlying problem (discussed earlier in the thread) has not been resolved, and the technician was therefore unable to get the "bent" wheel into better spec, and did not want the 2 wheels to be notably different, so set them both to as close to spec as the bent situation would allow. Just a guess, but if you were the technician, what would YOU do if the customer had not authorized a chassis integrity measurement?
Jim G
I actually asked them, after they replaced the control arm, that why didn't they do any measurements and the answer I got from them was some BS that they are not able to do it blablabla. I'm taking my car to an independent indie shop next week and will let them to take a look at it. I'm quite sure that the dealer just doesn't care enough to get anything done, because I can't find a reason why they didn't let the right rear camber be at -1°50' and then just adjust the left rear to -1°50 as well or even better to around -1°. The dealer had no experience with this kit beforehand and truth to be told - the camber is within the spec, so I guess they just didn't bother with it.
By the way, the car does drive and accelerate better than it did before. I tried a few hard pulls from stop and usually before the camber kit one side wanted to step out, but now the car pulls forward nicely. I guess that was also the reason why my car got sideways on straight road accelerations since owning it.
I actually asked them, after they replaced the control arm, that why didn't they do any measurements and the answer I got from them was some BS that they are not able to do it blablabla. I'm taking my car to an independent indie shop next week and will let them to take a look at it. I'm quite sure that the dealer just doesn't care enough to get anything done, because I can't find a reason why they didn't let the right rear camber be at -1°50' and then just adjust the left rear to -1°50 as well or even better to around -1°. The dealer had no experience with this kit beforehand.
I am thinking that it may take an auto body shop with a chassis straightener to realy measure up your car's chassis-wheel alignment, and figure out what happened to make proper camber apparently impossible to achieve. I'm certainly no car chassis expert but possible causes of this kind of situation could be:
- The car's wheel previously hit a curb or other surface really hard
- The car was previously hit in an unreported "minor" accident, and the repair work done did not detect, or detected but simply did not repair some damage that went beyond the wheel into the suspension or chassis, because the repair would have been costly
It it were me owning and driving the car, I'd want to figure out what was going on.
I am thinking that it may take an auto body shop with a chassis straightener to realy measure up your car's chassis-wheel alignment, and figure out what happened to make proper camber apparently impossible to achieve. I'm certainly no car chassis expert but possible causes of this kind of situation could be:
- The car's wheel previously hit a curb or other surface really hard
- The car was previously hit in an unreported "minor" accident, and the repair work done did not detect, or detected but simply did not repair some damage that went beyond the wheel into the suspension or chassis, because the repair would have been costly
It it were me owning and driving the car, I'd want to figure out what was going on.
Jim G
I really hope the situation is not this bad as you make it sound. This kit should give me the adjustability of +/- 3° so I can't find a single reason why my car can't have a more positive camber even if something is messed in the chassis... I'll update this thread next week when I get my car checked, again. Meanwhile other members rear camber specs are welcome.
I also just sent an e-mail to the dealer asking why they went with this specific setup. I'll report back when I get a reply.
My rears are wearing evenly
Some of the wear on the inside is from the factory toe spec which is a fair amount of toe out
The dealer will generally dial it back to spec which I find to be too much toe out and negative camber for my personal preference on the street
I don't know what kind of alignment machine they are using but I would think a dealership has some fairly up to date equipment. The machine we use will provide you with plenty of information to diagnose something that is bent. It won't necessarily tell you what is bent but you can use all the values to figure something out. I doubt the tech that did the alignment really understands everything going on. There is no reason it should be that far out of spec, its going to wear the tires on the inner edge. When you accelerate hard and the *** end squats down the camber will go even farther negative. Somebody with common sense and a proper understanding of vehicle suspension needs to look at it and find the bent component. Using aftermarket bushings to correct the alignment is just putting a band aid on the bigger issue. I recently did an e55 that had LR toe out and negative camber out of spec. Toe was set as far as adjustment would allow and was still out. Camber was off by .5 degrees. Based on position of toe link it seemed like the vehicle had taken an impact on the left rear corner impacting the upper, rear edge of the wheel. After removing the inner trunk liner it was confirmed that there had been previous body work done on that area. Sliding the car into a curb typically results in the bottom of the wheel being pushed in and creating excessive positive camber. A hit to the upper portion will result in negative camber. So to get negative camber like you have there aren't many options. Either the spindle is bent, highly likely as this is the most common piece I have replaced for rear alignment issues. The upper control arm bent, less likely but it happens, it can be measured end to end from center of mounting holes and compared to the other side. Or the lower control arm got longer, no clue how the hell that would ever happen. everything on the right side is the same as the left side. Take measurements and the part that doesn't match the left side part should be replaced.
Hopefully that makes sense, too many beers right now.
Oh, and if you really don't know what the hell is going on and just need a print out you can reposition the sensor on the wheel to get the value you want. This is common practice at shady alignment shops.
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