Brake Rotor Question
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c63
Brake Rotor Question
Hello All,
I'm new to the forum having just bought my first AMG, a 2008 C63. It's without question the most fun car I have owned. I appreciate the value of a good forum and I'm happy to find so many involved and knowledgeable owners here.
Yesterday, on the way to the dealer to have a warranty issue repaired, the check brake pad light came on so of course they pushed me for a brake job. The service writer explained that the front rotors are just at minimums and can't be reused. I have not measured them myself yet, but I'll assume they are at least close.
So here is my question: The "minimum" (the value stamped on the circumference of the rotor) appears to be the minimum thickness to which a new set of pads can be installed. That would be different in my mind from the minimum value that is functionally acceptable, given that the next set of pads will further wear the rotor well below the "minimum". The parts guy told me that most folks get two pad sets per rotor. It would seem to me that the minimum is then 50% of that "functionally acceptable" number. So my point would be that, give or take a thousandth or two, there ought to be some flex in that spec. for an involved owner.
I get that brakes are important, but I'm loath to toss a good set of rotors. My years on this Earth have taught me to approach dealerships with grains of salt. I'd appreciate the opinions of others on this matter.
Thanks
SF
I'm new to the forum having just bought my first AMG, a 2008 C63. It's without question the most fun car I have owned. I appreciate the value of a good forum and I'm happy to find so many involved and knowledgeable owners here.
Yesterday, on the way to the dealer to have a warranty issue repaired, the check brake pad light came on so of course they pushed me for a brake job. The service writer explained that the front rotors are just at minimums and can't be reused. I have not measured them myself yet, but I'll assume they are at least close.
So here is my question: The "minimum" (the value stamped on the circumference of the rotor) appears to be the minimum thickness to which a new set of pads can be installed. That would be different in my mind from the minimum value that is functionally acceptable, given that the next set of pads will further wear the rotor well below the "minimum". The parts guy told me that most folks get two pad sets per rotor. It would seem to me that the minimum is then 50% of that "functionally acceptable" number. So my point would be that, give or take a thousandth or two, there ought to be some flex in that spec. for an involved owner.
I get that brakes are important, but I'm loath to toss a good set of rotors. My years on this Earth have taught me to approach dealerships with grains of salt. I'd appreciate the opinions of others on this matter.
Thanks
SF
Member
Joined: Jun 2005
Posts: 81
Likes: 0
From: Toronto
06 C55, 15 S550, 16 G550
Hello All,
I'm new to the forum having just bought my first AMG, a 2008 C63. It's without question the most fun car I have owned. I appreciate the value of a good forum and I'm happy to find so many involved and knowledgeable owners here.
Yesterday, on the way to the dealer to have a warranty issue repaired, the check brake pad light came on so of course they pushed me for a brake job. The service writer explained that the front rotors are just at minimums and can't be reused. I have not measured them myself yet, but I'll assume they are at least close.
So here is my question: The "minimum" (the value stamped on the circumference of the rotor) appears to be the minimum thickness to which a new set of pads can be installed. That would be different in my mind from the minimum value that is functionally acceptable, given that the next set of pads will further wear the rotor. The parts guy told me that most folks get two pad sets per rotor. It would seem to me that the minimum is then 50% of that "functionally acceptable" number. So my point would be that, give or take a thousandth or two, there ought to be some flex in that spec. for an involved owner.
I get that brakes are important, but I'm loath to toss a good set of rotors. My years on this Earth have taught me to approach dealerships with grains of salt. I'd appreciate the opinions of others on this matter.
Thanks
SF
I'm new to the forum having just bought my first AMG, a 2008 C63. It's without question the most fun car I have owned. I appreciate the value of a good forum and I'm happy to find so many involved and knowledgeable owners here.
Yesterday, on the way to the dealer to have a warranty issue repaired, the check brake pad light came on so of course they pushed me for a brake job. The service writer explained that the front rotors are just at minimums and can't be reused. I have not measured them myself yet, but I'll assume they are at least close.
So here is my question: The "minimum" (the value stamped on the circumference of the rotor) appears to be the minimum thickness to which a new set of pads can be installed. That would be different in my mind from the minimum value that is functionally acceptable, given that the next set of pads will further wear the rotor. The parts guy told me that most folks get two pad sets per rotor. It would seem to me that the minimum is then 50% of that "functionally acceptable" number. So my point would be that, give or take a thousandth or two, there ought to be some flex in that spec. for an involved owner.
I get that brakes are important, but I'm loath to toss a good set of rotors. My years on this Earth have taught me to approach dealerships with grains of salt. I'd appreciate the opinions of others on this matter.
Thanks
SF
Member
Joined: Jun 2005
Posts: 81
Likes: 0
From: Toronto
06 C55, 15 S550, 16 G550
The change brake light is an indicator for the brake pad only, when the light is on, there is still approx 25% pad life remaining. So driving 1000km is definitely fine, unless you are doing extreme braking, can probably drive few thousand kms.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 4,563
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C63 AMG
Does the car have performance package? Two piece front rotors?
It will have the min thickness stamped on them. Measure with a caliper to see how close you are. Mine (2pc) were down 1mm after 45K Km. I put new pads on all 4 corners and all was good. From the measurements I took, there is 3mm of wear from new to the limit. You should be able to get around 80K-100K Km from the front rotors.
If you don't have the 2pc rotors.. News ones are only 200 bucks... The 2ps are like 1300 each.
It will have the min thickness stamped on them. Measure with a caliper to see how close you are. Mine (2pc) were down 1mm after 45K Km. I put new pads on all 4 corners and all was good. From the measurements I took, there is 3mm of wear from new to the limit. You should be able to get around 80K-100K Km from the front rotors.
If you don't have the 2pc rotors.. News ones are only 200 bucks... The 2ps are like 1300 each.
MBWorld Fanatic!
Joined: Mar 2011
Posts: 1,601
Likes: 10
From: San Diego/San Francisco
AMG GLC63. Audi R8
Hello All,
I'm new to the forum having just bought my first AMG, a 2008 C63. It's without question the most fun car I have owned. I appreciate the value of a good forum and I'm happy to find so many involved and knowledgeable owners here.
Yesterday, on the way to the dealer to have a warranty issue repaired, the check brake pad light came on so of course they pushed me for a brake job. The service writer explained that the front rotors are just at minimums and can't be reused. I have not measured them myself yet, but I'll assume they are at least close.
So here is my question: The "minimum" (the value stamped on the circumference of the rotor) appears to be the minimum thickness to which a new set of pads can be installed. That would be different in my mind from the minimum value that is functionally acceptable, given that the next set of pads will further wear the rotor well below the "minimum". The parts guy told me that most folks get two pad sets per rotor. It would seem to me that the minimum is then 50% of that "functionally acceptable" number. So my point would be that, give or take a thousandth or two, there ought to be some flex in that spec. for an involved owner.
I get that brakes are important, but I'm loath to toss a good set of rotors. My years on this Earth have taught me to approach dealerships with grains of salt. I'd appreciate the opinions of others on this matter.
Thanks
SF
I'm new to the forum having just bought my first AMG, a 2008 C63. It's without question the most fun car I have owned. I appreciate the value of a good forum and I'm happy to find so many involved and knowledgeable owners here.
Yesterday, on the way to the dealer to have a warranty issue repaired, the check brake pad light came on so of course they pushed me for a brake job. The service writer explained that the front rotors are just at minimums and can't be reused. I have not measured them myself yet, but I'll assume they are at least close.
So here is my question: The "minimum" (the value stamped on the circumference of the rotor) appears to be the minimum thickness to which a new set of pads can be installed. That would be different in my mind from the minimum value that is functionally acceptable, given that the next set of pads will further wear the rotor well below the "minimum". The parts guy told me that most folks get two pad sets per rotor. It would seem to me that the minimum is then 50% of that "functionally acceptable" number. So my point would be that, give or take a thousandth or two, there ought to be some flex in that spec. for an involved owner.
I get that brakes are important, but I'm loath to toss a good set of rotors. My years on this Earth have taught me to approach dealerships with grains of salt. I'd appreciate the opinions of others on this matter.
Thanks
SF
MBWorld Fanatic!
Joined: Mar 2011
Posts: 1,601
Likes: 10
From: San Diego/San Francisco
AMG GLC63. Audi R8
Does the car have performance package? Two piece front rotors?
It will have the min thickness stamped on them. Measure with a caliper to see how close you are. Mine (2pc) were down 1mm after 45K Km. I put new pads on all 4 corners and all was good. From the measurements I took, there is 3mm of wear from new to the limit. You should be able to get around 80K-100K Km from the front rotors.
If you don't have the 2pc rotors.. News ones are only 200 bucks... The 2ps are like 1300 each.
It will have the min thickness stamped on them. Measure with a caliper to see how close you are. Mine (2pc) were down 1mm after 45K Km. I put new pads on all 4 corners and all was good. From the measurements I took, there is 3mm of wear from new to the limit. You should be able to get around 80K-100K Km from the front rotors.
If you don't have the 2pc rotors.. News ones are only 200 bucks... The 2ps are like 1300 each.
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Thread Starter
Newbie
Joined: Jun 2012
Posts: 5
Likes: 0
c63
Thanks for the comments guys. I do have the one piece rotors, BTW. I might have given the impression that I'd be likely to skimp on brake maintenance. I will not. I just want to understand the situation before I order parts.
I had a look this morning and came away no wiser for the effort. It is unclear to me whether the rotors are measured individually or as a pair. I looked at the edge of the rotors for a stamped marking and found none. I did find a "14" stamped on the inside of the inboard rotor. 14mm is greater that the lip.
I measured them as a pair and got 35.25 mm then measured the lip and got 36.1 mm. Wear appears to be less than 1mm between the two if one assumes the lip is unworn. On the other hand, if the 14mm is the spec for each rotor, then I'm significantly under.
I had a look this morning and came away no wiser for the effort. It is unclear to me whether the rotors are measured individually or as a pair. I looked at the edge of the rotors for a stamped marking and found none. I did find a "14" stamped on the inside of the inboard rotor. 14mm is greater that the lip.
I measured them as a pair and got 35.25 mm then measured the lip and got 36.1 mm. Wear appears to be less than 1mm between the two if one assumes the lip is unworn. On the other hand, if the 14mm is the spec for each rotor, then I'm significantly under.
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2012 C63;1971 280SE 3.5(Sold);2023 EQS 450 SUV 4 Matic (Wife's)
from james @ ACGSD
Front rotors 36mm; service limit 34mm; wear limit 33.4mm
You measure the total width of the rotor friction surfaces.
The spec is stamped on the outer lip/edge of the rotor.
Your rotors sound like they are fine for reuse.
Front rotors 36mm; service limit 34mm; wear limit 33.4mm
You measure the total width of the rotor friction surfaces.
The spec is stamped on the outer lip/edge of the rotor.
Your rotors sound like they are fine for reuse.
Thread Starter
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c63
Thanks Mort. I do appreciate your help.
The service limit and wear limits are what I was alluding to in my first post.
I looked carefully around the lip/edge/ circumference of the rotor and saw nothing. Oh well.
Dave
The service limit and wear limits are what I was alluding to in my first post.
I looked carefully around the lip/edge/ circumference of the rotor and saw nothing. Oh well.
Dave
