Wrong size tire installed
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Joined: Oct 2017
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From: Atlanta, Ga
2016 C450 AMG Sedan
Wrong size tire installed
i just noticed when the MB dealer replaced my front passenger tire he replaced it with a 245/40 instead of a 225/45 by mistake. This happened about 5 months ago. Should I be worried about any damage to the awd system? I’m driving up to the dealership in the morning to correct the situation.
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Joined: Feb 2016
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From: Portland, OR
C450, GLC43
i just noticed when the MB dealer replaced my front passenger tire he replaced it with a 245/40 instead of a 225/45 by mistake. This happened about 5 months ago. Should I be worried about any damage to the awd system? I’m driving up to the dealership in the morning to correct the situation.
No. 4 matic isn't as picky as some of the older Volvo and Subie AWD systems used to be.
I do think you should insist that they replace both front tires as the different sizes may have affected wear on the opposing tire. While the chances of this actually happening are small, the fact is they made a serious mistake. Running mismatched tires on front may not cause any mechanical harm but i'm sure it impacted handling of the vehicle. I'm surprised that the car didn't respond strangely under heavy braking or hard cornering. The mismatched front tires are a safety issue, one that they caused do to poor attention to detail.
You should be concerned about the competency of your service center. Do yourself a favor and find a good indy tire and wheel shop. Save the dealership for the warranty work only. If you're in a metro area with more than one MB dealer, then it's time to switch up.
Last edited by Mr. J; Aug 26, 2018 at 03:09 AM.
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Joined: Nov 2017
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2018 Mercedes C43 AMG Coupe
Just to reassure you. The difference in dimension is basically nil. 40% of 245 is ~= 35% of 225. That difference is what I run on my car vs stock anyway and it's a very common tire size for our cars.
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I'd disagree. Assuming the car has OEM rims, that means the front rim is 7.5" wide. According to various wheel/rim size calculators, e.g.:
https://www.tyresizecalculator.com/t...ize-calculator
a 245/40x18 should be on rim that's a minimum of 8" wide and, ideally, on a rim that's 8.5" wide.
I'd agree with the "Mr. J" posting that said the error is a handling/safety issue, albeit maybe not too serious an issue.
OTOH, since I know that at least some 8" rims fit the C43's front (my winter rims are such), it's good to know that a 245/40 probably won't cause any rubbing issues (IIRC, the 450 and 43's front suspensions are a little different). I've been trying to figure out what tire/rim sizes I can use to put a set of cup 2 tires on the car for track days and I'd like to get a little more "square" than the standard fitment.
https://www.tyresizecalculator.com/t...ize-calculator
a 245/40x18 should be on rim that's a minimum of 8" wide and, ideally, on a rim that's 8.5" wide.
I'd agree with the "Mr. J" posting that said the error is a handling/safety issue, albeit maybe not too serious an issue.
OTOH, since I know that at least some 8" rims fit the C43's front (my winter rims are such), it's good to know that a 245/40 probably won't cause any rubbing issues (IIRC, the 450 and 43's front suspensions are a little different). I've been trying to figure out what tire/rim sizes I can use to put a set of cup 2 tires on the car for track days and I'd like to get a little more "square" than the standard fitment.
