| pooklymdx |
| I have a 2004 MDX with 9300 miles and just had my front brake rotors milled. They were definitely warped. I have experience with this. The service manager of course told me that I must be hard on my brakes. I am certainly not. Acura did do a one time courtesy milling and replaced the pads. Anyone else out there see this?:( |
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| JeffK |
I have posted on this subject before.
First: Warped brake rotors are a WARRANTY ITEM. Service departments will try every which way to Sunday, to deny warranty coverage. But stick to you guns.
Second: Having said that, the correct procedure, especially with only 9300 miles, is to have the rotors REPLACED not turned, i.e., milled.
Turning a rotor takes "meat" off, making the rotor thinner and more susceptible to future warping.
JeffK |
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| DaleB |
| My dealer had no problem turning rotors and fitting new pads in front under warranty at 19K. |
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| kimsta |
| I had mine replaced, both the rotors and pads. Seems like it's a very common problem with the X. |
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| hondacuraworld |
quote:
Originally posted by JeffK
I have posted on this subject before.
First: Warped brake rotors are a WARRANTY ITEM. Service departments will try every which way to Sunday, to deny warranty coverage. But stick to you guns.
Second: Having said that, the correct procedure, especially with only 9300 miles, is to have the rotors REPLACED not turned, i.e., milled.
Turning a rotor takes "meat" off, making the rotor thinner and more susceptible to future warping.
JeffK
Generally service departments are mandated to cut the rotors if they are not warped. Why they would cut a warped rotor, :confused:
Remember that Acura dealers get paid to do warranty work, it doesn't come out of the dealership's pocketbook. It's in everybody's best interest for the dealer to perform the work.
I'd say that if you had an experience like that, it was just that isolated dealer with some strange issues. |
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| bb123 |
| Kimsta, it's not just a problem with the MDX, it seems to be a problem with many Hondas. My previous MDX, last three Accords and two Civics had to have their rotors resurfaced. It happens often enough to make me believe it's just a Honda thing. It's particularly annoying because I've always thought Honda brakes didn't stop all that well in the first place. |
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| JL_SS |
quote:
Originally posted by bb123
Kimsta, it's not just a problem with the MDX, it seems to be a problem with many Hondas. My previous MDX, last three Accords and two Civics had to have their rotors resurfaced. It happens often enough to make me believe it's just a Honda thing. It's particularly annoying because I've always thought Honda brakes didn't stop all that well in the first place.
It has been my experience that it is a Honda problem too. Have had an accord, a civic, a prelude, and a crv that have all had rotor warping problems with normal driving. Also annoying was that all had exhaust system heat shields rattling by 60K miles. |
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| jaomdx |
| I have a 2003 with 23k. I have had mine replaced under warranty twice! |
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| BlueStreak |
13.3K on my 2003 and they were replaced. Dealer said after turning they would not meet spec, so off they came. New pads also installed.
Compare this to my 1994 Accord Sedan EX which went 132K before the front pads went (same driving style) and they never warped. And the rotors were will 80% of spec when I replaced them.
Honda's going cheap on us, and they are by no means the only ones..... |
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| JL_SS |
quote:
Originally posted by BlueStreak
13.3K on my 2003 and they were replaced. Dealer said after turning they would not meet spec, so off they came. New pads also installed.
Compare this to my 1994 Accord Sedan EX which went 132K before the front pads went (same driving style) and they never warped. And the rotors were will 80% of spec when I replaced them.
Honda's going cheap on us, and they are by no means the only ones.....
I would guess they started going cheap in 1995 then. My Accord was a 95 and I had numerous warping issues. |
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| fchao |
Since the brake is related to safety, anyone can educate me how to tell there are problems about the rotors.
THX |
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| DaleB |
Depending on the severity, during normal braking you would notice some vibration or even shimmy through the steering wheel possibly accompanied by pulsations through the brake pedal.
The normal cure is to have the rotors turned or replaced, along with new brake pads to ensure they wear in smoothly.
Acura turned my front rotors (typically the culprits, as they do most of the braking) and replaced the pads as a warranty claim at 19K.
So far it works just fine.
Don't confuse pulsations through the brake pedal during very hard or panic braking, which is likely the normal function of the anti-skid braking system.
There seems to be a higher than average complaint among MDX owners, but the MDX is far from being alone with this problem.
Lots of discussion on this over the years, if you do some searches. |
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| feliz |
| It seems to plague Hondas/Acuras more than some brands, although I've never had a problem. I follow a few forums though and can say that it's a problem with other brands as well, generally believed to be a result of manufacturers trying to save weight using CAd etc. Take a look at rotors from the 70s and 80s and the modern rotors and you will see what I mean. The skimpiest rotors I've ever seen are the rotors in the TSX. I changed my mind about buying a Toyota Tundra based on all the brake problem I read about in the forums. |
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| teamTMS |
I know this is a late post on this topic but ...
I had a great experience. My front brakes rotors warped. Open Road Acura cut them and I got the MDX back. It started to make noises while I was driving. Went back the next day, they replaced the rotors with new ones ... all under warranty! |
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| Fabvsix |
| The Acura CL Type S has ton of customers with "warped rotors" ! Mine were shaved, pads changed and 3 months later, they are warped again. My 1998 Accord Coupe V6EX NEVER had warped brake issues and the CL was $34,000.00 plus........This is where they are cutting corners so we get a bang for our buck ! :rolleyes: |
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| dipersp |
I hate to say it, but this plagues all cars to some degree. I went through rotors all the time on my Maxima - with 96k on the clock, I think I'm on the four or fourth set? I couldn't use factory rotors as I would barely get 15k out of them.
I also had a few Fords that were bad. Keep in mind, any time the rotors are hot from braking, stay away from water. Auto car washes (And manual, if you wash right after driving) are terrible. Also, if you need to use your brakes HARD, make sure and let the car roll a little after stopping. If you hold the pedal hard after a hard braking, the rotors will cool, except for that spot under the pads, and will generally warp.
Common sense is the best policy, but even that doesn't always work. |
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| Fabvsix |
| I think washing the vehicle immediately after driving, your asking for trouble......I concur ! |
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| perk |
I'm at 19k and my rotors are warped. Called the dealer yesterday to schedule maintenance to fix brakes and do the emissions recall. The dealer said that brakes are a "wear item" and only covered up to 12k miles. I mentioned that I had read about many other folks having the same problem and hoped that he would replace my rotors and pads under warranty. He said "AcuraMDX.org does not speak for dealers." I told him that I knew that and well understood that AcuraMDX.org was a user's site.
He eventually agreed to "take a look at them." Can someone show me where it says that brake rotors are a WARRANTY item. It sure would be helpful. Thanks. |
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| hondacuraworld |
| Gray area......I would tell you to call Acura customer relations. |
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| DaleB |
quote:
Originally posted by hondacuraworld
Gray area......I would tell you to call Acura customer relations.
My dealer didn't blink. Same approximate mileage they resurfaced the front rotors and stuck in new pads. I did not beg, scream, or threaten. Just told them I had a problem. |
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| JeffK |
Stick to you guns.
Wrapped rotors are a warranty item. No question about it. |
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| BlueStreak |
quote:
Originally posted by perk
I'm at 19k and my rotors are warped. Called the dealer yesterday to schedule maintenance to fix brakes and do the emissions recall. The dealer said that brakes are a "wear item" and only covered up to 12k miles. I mentioned that I had read about many other folks having the same problem and hoped that he would replace my rotors and pads under warranty. He said "AcuraMDX.org does not speak for dealers." I told him that I knew that and well understood that AcuraMDX.org was a user's site.
He eventually agreed to "take a look at them." Can someone show me where it says that brake rotors are a WARRANTY item. It sure would be helpful. Thanks.
:bsflag: I had 13K on mine when they were REPLACED under warraty. |
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| perk |
| As a followup to my earlier post, my rotors and pads were replaced under warranty by the dealer yesterday. They resisted at first, but then gave in and did the work at no cost. |
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| JeffK |
| GLAD TO HEAR THAT!!! |
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| badulla |
From an owner perspective (well future owner anyway) I would hope warped rotors are a warranty issue.
That said, most people I know who have had warped rotors in any vehicle was caused by the user. Either by overheating the rotors (track), or by driving hard and then going through a car wash. The car wash thing happens a lot.
So to some extent, I can see an argument for it not being covered.
Just playing devil's advocate. |
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| badulla |
From an owner perspective (well future owner anyway) I would hope warped rotors are a warranty issue.
That said, most people I know who have had warped rotors in any vehicle was caused by the user. Either by overheating the rotors (track), or by driving hard and then going through a car wash. The car wash thing happens a lot.
So to some extent, I can see an argument for it not being covered.
Just playing devil's advocate. |
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| DaleB |
quote:
Originally posted by badulla
From an owner perspective (well future owner anyway) I would hope warped rotors are a warranty issue.
That said, most people I know who have had warped rotors in any vehicle was caused by the user. Either by overheating the rotors (track), or by driving hard and then going through a car wash. The car wash thing happens a lot.
So to some extent, I can see an argument for it not being covered.
Just playing devil's advocate.
I don't really see them as a warranty item unless they had obvious defects like fractures, etc. I suspect some dealers are aware warping to this degree goes beyond normal expectations, and perhaps Acura allows a little lattitude in that regard. It might be more of a 'goodwill gesture'. If it was a recall, or clearly a warranty issue, every dealer would be working the disks on every one that comes in. I don't think that is the case.
Also, I am sure they will only keep doing it up to a certain mileage and/or time (the ones that do it, that is). |
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| MesaBeige |
I have no idea. But......
I have had lots of Honda cars over the years and I used to have warped rotors. I also used to wash my cars when the brakes were still hot from driving/braking. I have been very conscious to only wash my cars now when the brakes are completely cool and I have not had problems with my Honda cars in the last seven years.
Coincidence, I don't know but I will keep doing what I'm doing.
If somebody knows why they warp please let us know.
MB- |
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| badulla |
| Yeah cold water on hot rotors is a bad thing. Always let them cool off before you wash them....and let them cool off before you go through one of those washing stations. I would recommend avoiding those machine washing stations anyway, but if you must then stop then vacuum out the car first and give your rotors 15 minutes or so to cool down. Depending on how hot they are to start you may need more than 15 minutes for them to cool. |
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| JeffK |
Just my $.02:
Imagine you are driving on I -95 in Florida (or I-95 in the North during the summer). It is 90 degrees outside.
A thunder shower hits - you go through a puddle
Are you suggesting that Acura has manufactured and sold brake rotors that doesn't anticipate this common occurrence?
I think not.
As I have posted before, very few cars seem to have the problem with brake rotors that Honda/Acura does.
That is not to say that the problem does not exist with other cars - but rather it seems all to common with Honda/Acura.
My conclusion as posted before: This is a manufacturing defect that is covered by the 4 year/48,000 mile warranty. |
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| badulla |
Two issues there.
1. When it rains the water is not as cold as from your hose, nor is it being shot directly at your rotors.
2. It is evenly hitting your rotors (on both sides), unlike when you are hosing down your car. This "even" distribution is key.
I'm not saying that Honda makes the best brakes, just merely saying that spraying your hot brakes with the cold hose water can be a major cause of rotor warping, no matter who the manufacturer is. |
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| norcalchuck |
quote:
Originally posted by BlueStreak
:bsflag: I had 13K on mine when they were REPLACED under warraty.
I just had mine replaced at 13,800. Noticed a significant vibration on braking at highway speed coming back from Lake Tahoe this weekend. They wanted to resurface them, but I said that I wanted new rotors since it is a wear item and I will be replacing them sooner if they are turned.
They factory did authorize the replacement, but the service manager grilled me about how the car is driven and said that I should be downshifting when driving through the mountains. I drive to Lake Tahoe for skiing--never had a car that under normal conditions, went through rotors like this.
He said engineering had called and wanted the specifics as they are concerned over these issues, but my feeling is that the expected use of an SUV includes mountain driving, and barring towing heavy loads, they should design in for those conditions.
For now it is not an issue, but I guess the next set of warped rotors will be. |
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| cmjcrj700pilot |
| :) Have you had your tires rotated in the last 9300 miles??? If you have there is your issue. When the rotors are warm and the wheels are reinstalled and overtorqued, the result with be warped rotors. Hand tightening vs. an impact wrench will prevent the problem in the future. |
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| cmjcrj700pilot |
| :) Have you had your tires rotated in the last 9300 miles??? If you have there is your issue. When the rotors are warm and the wheels are reinstalled and overtorqued, the result with be warped rotors. Hand tightening vs. an impact wrench will prevent the problem in the future. |
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| sidewinder |
quote:
Originally posted by perk
I'm at 19k and my rotors are warped. Called the dealer yesterday to schedule maintenance to fix brakes and do the emissions recall. The dealer said that brakes are a "wear item" and only covered up to 12k miles. I mentioned that I had read about many other folks having the same problem and hoped that he would replace my rotors and pads under warranty. He said "AcuraMDX.org does not speak for dealers." I told him that I knew that and well understood that AcuraMDX.org was a user's site.
He eventually agreed to "take a look at them." Can someone show me where it says that brake rotors are a WARRANTY item. It sure would be helpful. Thanks.
Thats exactly what I'm getting from my dealer on my warped rotors. They are saying its covered for 12mos or 12K. I explained to him many owners had this problem and gotten the rotors resurface or replaed. They are going to contact the Acura district rep on this and get back to me. What other options do I have if they still say no?
EDIT: just got a call back from service advisor and he says Acura SE zone district mgr says they will not cover it under the warranty. But they will go 50/50 on resurfacing cost due to the low mileage 18K(wife's car and she don't drive much). I don't undersand how others have gotten theirs replaced without a single problem and I run into a brick wall. What other options do I have on this? |
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| JeffK |
I have posted before: Stick to your guns!
Rotors do not warp due to wear. How can this then be a wear item?
Of course it cannot be!
Unlike brake pads, tires, windshield wiper blades that wear down with time, here we are talking about a DEFECTIVE PART
It can only be a "wear item" if Acura now takes the position that through time all rotors warp and warping is normal wear.
This of course is non-sense. That is why the cost of the 48 months/48,000 mile warranty is built into the price.
Of course a dealer will try to convince everyone that as many items as possible are "wear" items.
Seems a shame - but on the other hand no one has every confused an Acura with a Lexus when it comes to "total luxury care".
Acura has a long way to go and in reality they may not ever want to be a "true" luxury car, just a wannabe with one damn good product the MDX and the balance glorified Honda's.
JeffK |
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| sidewinder |
Spoke with Client Services and they said there are many reasons why rotors warp(i.e. driving habits, temperature issues) and that each case is handled on an individual basis. She recommended I have another dealer look at it for 2nd opinion but I'm not confident if it will make any difference.
She said only reason a rotor would be replaced is if they were found defective by the dealer. I don't see how they can tell if a warped roter is 'defective'. I thought a warped rotor was a warped rotor. In anycase she said they do not have the authority to overrule the Acura zone manager. I don't want to make a big stink out of this but I believe I'm out of options at the momemt. :( |
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| DaleB |
quote:
Originally posted by sidewinder
Thats exactly what I'm getting from my dealer on my warped rotors. They are saying its covered for 12mos or 12K. I explained to him many owners had this problem and gotten the rotors resurface or replaed. They are going to contact the Acura district rep on this and get back to me. What other options do I have if they still say no?
EDIT: just got a call back from service advisor and he says Acura SE zone district mgr says they will not cover it under the warranty. But they will go 50/50 on resurfacing cost due to the low mileage 18K(wife's car and she don't drive much). I don't undersand how others have gotten theirs replaced without a single problem and I run into a brick wall. What other options do I have on this?
My car was 18 mos. old, with 19K miles. Dealer did not blink an eye. Resurfaced and installed new pads. This was not the selling dealer either. Still works great (as it should) 7K miles later. |
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| sidewinder |
quote:
Originally posted by DaleB
My car was 18 mos. old, with 19K miles. Dealer did not blink an eye. Resurfaced and installed new pads. This was not the selling dealer either. Still works great (as it should) 7K miles later.
Hmm...I wonder if this has anything to do with age of the car? Mine will be 4yr next January although it only has 18K on it. I would think age of the car would be irrelevant. Are you sure it was covered under the warranty or if the dealer did it out of goodwill and covered it themselves? |
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| badulla |
The age of your X may have something to do with their decision. They are probably thinking that if you didn't have problems in 3 prior years then the rotor is not defective. The problem with that thinking is that you only have 18k miles on the vehicle!
I would call Acura HQ yourself and complain as well as show up at the dealership and complain. May not help but isn't going to hurt either. And I would definately go to another dealer, explain your dissatisfaction with your current dealer while you are there too, they'll want to take your business from them. And if all it will take is new rotors they will probably do it.
Good luck.
Dan |
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| JeffK |
Dear Posters:
Warped rotors are almost always caused by a drastic change in heat.
Having said that, most cars do not suffer from warped rotors.
Change in temperature is a normal condition that should be designed for.
Evidentially MDX's suffer an abnormal number of warped rotors. The cost must be considerable to Acura.
Hence the attempt at deny responsibility.
Warped rotors are the result of manufacturing or design defects - not wear and tear!
It is not either the duty or obligation of an owner to explain why or how the rotors warped.
This is not a wear item - age has nothing to do with whether a rotor will or will not warp.
This is an item that is covered under the bumper to bumper warranty.
Finally, while under warranty I would not accept a turning of the rotor. Turning only makes the rotor thinner and hence more prone to warping in the future.
You MDX is still under warranty. Insist that Acura lives up to its warranty obligations and have them replace the defective and damaged rotor.
JeffK |
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| badulla |
I agree with you for the most part Jeff, but while rotors are not a wear item, if they warp it is sometimes caused by the user.
As mentioned before...trying to wash your car while the rotors are hot can easily warp them, hence drastic change in temperature. I'm not saying that this is sidewinders case, but many people warp their rotors this way...and the dealers know this. |
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| JeffK |
Dear Badulla:
You posted:
As mentioned before...trying to wash your car while the rotors are hot can easily warp them, hence drastic change in temperature. I'm not saying that this is sidewinders case, but many people warp their rotors this way...and the dealers know this.
I do remember your prior post!
Two comments:
If you go through a car was, then water hits both sides of the rotor simultaneously. So the only instance where car washing might be a factor is someone who is riding the brakes on a hot day, jumps out of his car and then proceed to immediately hose down his wheels!
On that rare occasions, I agree with you and the dealer may not be responsible.
For the 99.9% of the other times he is!!!!
I just think this is a design flaw with the MDX and rather than step up to the plate, Acura is trying every which way but lose to deny responsibility.
BTW, as I previously posted, I had the same problem with my Mercedes. They immediately replaced the rotors (they had over 30,000 miles on them) no questions asked.
Again, no one is confusing Acura with other luxury brands - see also the problem with transmissions and there initial denial of responsibility.
If Acura did not have the MDX, the show rooms would be empty and Acura could pack up and go home!
JeffK |
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| badulla |
Most car washes...at least around me...have guys that take your money and then spray the hose right on your wheels/rotors. So if this is the case it is only hitting on side and therefore a risk.
I also think you'd be surprised at how many people wash their cars at home immediately after driving.
That said.....I hear what you are saying Jeff and agree that rotors should be covered especially if it is a first time occurance for the vehicle/owner regardless of the mileage. If someone repeatedly had the problem then I can see the dealer cracking down on that person. |
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| DaleB |
quote:
Originally posted by badulla
Most car washes...at least around me...have guys that take your money and then spray the hose right on your wheels/rotors. So if this is the case it is only hitting on side and therefore a risk.
I also think you'd be surprised at how many people wash their cars at home immediately after driving.
That said.....I hear what you are saying Jeff and agree that rotors should be covered especially if it is a first time occurance for the vehicle/owner regardless of the mileage. If someone repeatedly had the problem then I can see the dealer cracking down on that person.
A car wash can be a bad choice for a variety of reasons. But I can not remember the last time I was in any car, fresh off the freeway, rotors a blazin'...that I did not have to wait in line to get a car wash.
I think it is thinner rotor material myself. Or maybe there is an alloy that could be added to reduce it, but it was a cost decision. Whatever, the biggest cause of warpage is repeated over braking. |
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| sidewinder |
| I called client services and spoke to a different rep and he admitted they get calls on rotor issues and again proceeded to tell me that rotors are 'wear and tear' item. Any recommendations on what action I need to take next? Client Services is so far useless and the Acura SouthEast Zone manager refuses to cover it. ($50 to resurface rotor without pads) |
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| JeffK |
Advise them that:
1) A proper rotor wears, does not warp.
2) If they refuse to replace advise them that you will go to the better business bureau and NHTSB as you believe warped rotors are a safety issue.
I suspect mention the words safety and NHTSB and the possibility of a general recall, and you will see plenty of action pronto!
Good luck!
JeffK |
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| badulla |
Drive the MDX right through the front of the dealership...then blame it on the rotors they wouldn't fix. :D
First...call another dealer and see what they say. Hell call any other dealer, doesn't even have to be Acura.
Then go there and make them explain to you why and how they consider it a wear item. Print out examples from this board about rotors warping on the MDX and show them if they are still putting up a stink. Talk to the service manager...and then make him call the Zone manager while you are there.
Just my advice.....wish I could go with you....I love beating up on service guys. |
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| sidewinder |
JeffK, I'll be calling the parts/service director tomorow and see what he has to say when I bring up those words. But seriously do u think a warped roter is a safety issue that would warrant a recall. Anyways will see what he has to say.
Badulla, let me think about that...hmm...I think I would have lot more to worry about then a warped rotor. :D I actually went to the Honda dealer across the street and spoke to a service advisor there and he gave me the same story 12mos/12k. Oh well. |
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| badulla |
I think mentioning a recall would work better with Corporate than it would the parts guy.
So have you called another Acura dealer? I'm going to make a call myself because now I am curious. Hell...PM me your dealers number and I'll call them too for a little harrassment. :) |
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| TheyCallMeBruce |
quote:
Originally posted by badulla
Most car washes...at least around me...have guys that take your money and then spray the hose right on your wheels/rotors. So if this is the case it is only hitting on side and therefore a risk.
I also think you'd be surprised at how many people wash their cars at home immediately after driving.
That said.....I hear what you are saying Jeff and agree that rotors should be covered especially if it is a first time occurance for the vehicle/owner regardless of the mileage. If someone repeatedly had the problem then I can see the dealer cracking down on that person.
Next time you get home, or get to work, get out of the car and immediately touch the front rotors through the wheel openings. Its not like they're so hot that spraying water will sizzle them, nor warp them when exposed to water, on one or both sides. You will only get extreme reaction to water exposure if you finish a high-speed downgrade run of several grade percents. Even 3 minutes of freeway driving will cool them off sufficiently to avoid sizzle-warp, and 10 minutes of free-moving local driving will do the same.
I hae some experience with this because as an ignorant 17 year old, I'd "cool" the rotors w/ gas station water when I've come down the local mountains so fast that the brakes were fading. The water basically explodes on contact and the entire caliper & rim area gets a severe steam cleaning. Very impressive to bystanders, but eventually I figured out the pattern and stopped doing that. I'd drive slowly on level areas for 10 minutes til the rotors were warm to the touch before continuing to jam downhill. |
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| RobK |
JeffK,
quote:
Originally posted by JeffK
Warped rotors are the result of [b]manufacturing or design defects - not wear and tear!
It is not either the duty or obligation of an owner to explain why or how the rotors warped.
This is not a wear item - age has nothing to do with whether a rotor will or will not warp.
I have to disagree with you. Well, at least partly. Design and manufacturing defects certainly can cause pulsation. However, those two things are not always the cause.
Driver behaviour can also be to blame, as does normal wear of the rotor.
What causes pulsation is thickness variation on each side of the rotor. "warping" is not really the correct term to use because the word warp tends to be understood to mean the entire rotor (ie., both surfaces) "warp" in the same direction at the same spot on the rotor. This would not cause a pulsation on a lot of vehicles because the caliper design allows the caliper to slide, and "follow" the warpage of the rotor.
What can cause thickness variation, among defects in the material itself, is heat. So for example, if a person rides their brakes hard on the way home, getting the caliper and pads good and hot, then parks the vehicle, most of the rotor is able to dissipate the heat quickly except the part that is underneath the caliper. This tends to happen more easily as a rotor wears because it gets thinner with age and therefore cannot dissipate heat as well.
quote:
Finally, while under warranty I would not accept a turning of the rotor. Turning only makes the rotor thinner and hence more prone to warping in the future.
By your own statement here, you seem to negate what you say about wear not being a cause of pulsation. Your statement is correct, as a rotor gets thinner (either by machining or normal wear) it is not able to dissipate heat as well as when new, and therefore more susceptible to pulsation.
So there's my $.02. In any case, it's good to argue with you again JeffK!
-Rob- |
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| XStatic |
You would think with all the brake issues apparently reported manufacturers would add a blaring horn to alert idiot drivers that drive with their left foot resting on the brake. It can't be good for the rotors and it is a pain to drive behind them since it makes it hard to tell if they are slowing down.
According to this article http://www.stoptech.com/whitepapers...rotors_myth.htm
rotors don't really "warp" they get high spots from brake pad material.
This article says that "The driver can feel a 0.0004" deposit or TV on the disc. 0.001" is annoying. "
It also says that the likelyhood of reoccurance is high afther milling since "The trouble with this procedure is that if the grinding does not remove all of the cementite inclusions, as the disc wears the hard cementite will stand proud of the relatively soft disc and the thermal spiral starts over again. "
Is it generally the front or rear that pulse? It looks like the rear disk is about 1/3 the thickness of the front. How does this impact its risk to build up? |
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| RobK |
quote:
Originally posted by XStatic
According to this article http://www.stoptech.com/whitepapers...rotors_myth.htm
rotors don't really "warp" they get high spots from brake pad material.
XStatic, you're right, and thanks for offering that article. It agrees with what I said in my earlier message - that rotors don't really warp, but the two surfaces exhibit a thickness variation that, when the brake pads ride over them during braking, pushes the caliper piston back slightly. You feel that in the pedal as a pulsation.
quote:
Is it generally the front or rear that pulse? It looks like the rear disk is about 1/3 the thickness of the front. How does this impact its risk to build up?
It is generally the front that pulsate. True, the thickness of the rotor is greater up front. The reason for the extra thickness and the reason for the likelyhood of a front rotor causing a pulsation is because (generally) 60-70% of braking force is done by the front calipers, not the rear. So the front builds up heat much more quickly than the rear. And as we already know, the intense heat is one reason for pulsation. |
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| JeffK |
Dear XStatic and XStatic:
Well you can teach an old dog new tricks!
Great post and article, which I just read. I stand corrected.
Thank you for this information! It is appreciated. In fact I have printed the article.
So the culprit seems to be heat and improper brake break in.
Interesting, if the problem surfaces (no pun intended) then "turning the rotor" is only a temporary fix, as the material in the disc has been adversely affected and the problem will re-occur.
So I guess the cure is:
Better instruction on break in of brake pads - read owner's manual and it is basically silent except "do not brake hard for first hundred miles"
Replacing the rotors.
JeffK |
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| DaleB |
quote:
Originally posted by JeffK
Dear XStatic and XStatic:
So the culprit seems to be heat and improper brake break in.
JeffK
Too many panic stops can have the same effect, or barreling down a mountain pass and riding the brake. Rotor and drums have always been 'wear items' for as along as I can remember.. which is not as long as it use to be... :D |
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| teckniks |
sometimes when im on the highway and im going 70mph and when for example an idiot hits his brakes or cuts me off i hit the brakes and go down to about 50mph my steering wheel would shake.
does this mean i have warped rotors? how can you tell? |
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| TheyCallMeBruce |
quote:
Originally posted by teckniks
sometimes when im on the highway and im going 70mph and when for example an idiot hits his brakes or cuts me off i hit the brakes and go down to about 50mph my steering wheel would shake.
does this mean i have warped rotors? how can you tell?
A tell-tale indication of warped rotors is very noticeable pulsation of the brake pedal when braking. The effect is in proportion to how hard you are breaking, but you would still feel it in every single instance, whether slightly, or hard-braking. It is also speed sensitive such that its would be rapid pulsations at high speeds and slower pulsations at low speeds. If your rotors are straight, you should experience absolutely no sensation of pulsation regardless of how hard you brake, until you get to the point that the ABS system engages (emergency braking) and the electronic pulsations are artificially created on your behalf to prevent skidding and sliding.
Steering wheel vibrations while braking (in the absence of brake-pedal pulsations) could be more an issue of wheel alignment. Run you hands over the treads and see if you notice saw-toothing either laterally or transversly, the former reflecting a wheel off-balance, and the later an exaggerated toe-in due to curb hits. Either way, you need either an alignment or balance job, or both. |
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| teckniks |
quote:
Originally posted by TheyCallMeBruce
A tell-tale indication of warped rotors is very noticeable pulsation of the brake pedal when braking. The effect is in proportion to how hard you are breaking, but you would still feel it in every single instance, whether slightly, or hard-braking. It is also speed sensitive such that its would be rapid pulsations at high speeds and slower pulsations at low speeds. If your rotors are straight, you should experience absolutely no sensation of pulsation regardless of how hard you brake, until you get to the point that the ABS system engages (emergency braking) and the electronic pulsations are artificially created on your behalf to prevent skidding and sliding.
Steering wheel vibrations while braking (in the absence of brake-pedal pulsations) could be more an issue of wheel alignment. Run you hands over the treads and see if you notice saw-toothing either laterally or transversly, the former reflecting a wheel off-balance, and the later an exaggerated toe-in due to curb hits. Either way, you need either an alignment or balance job, or both.
thank you!! i will check out if i have any brake pedal vibrations and check the tire tread and pressure and see if i will need an alignment. ;) |
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| Fabvsix |
Techniks:
YOU have warped rotors ! The vibration will ONLY occur at higher speeds as you described and the alarming COMPLAINTS from other Acura owners, which I'm one of the Acura CL Type S that has crappy brakes and TONS of complaints due to WARPED rotors described EXACTLY AS YOU DID. Your X is NOT out of allignment. You wouldn't be SO lucky ! Trust me ! One of two area of concerns with Honda's/Acura's:
WARPED ROTORS
TRANSMISSION FAILURES !
Hope this doesn't burst any die hard Acura bubbles ! :( :( :( :( |
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| TheyCallMeBruce |
quote:
Originally posted by Fabvsix
Techniks:
YOU have warped rotors ! The vibration will ONLY occur at higher speeds as you described and the alarming COMPLAINTS from other Acura owners, which I'm one of the Acura CL Type S that has crappy brakes and TONS of complaints due to WARPED rotors described EXACTLY AS YOU DID. Your X is NOT out of allignment. You wouldn't be SO lucky ! Trust me ! One of two area of concerns with Honda's/Acura's:
WARPED ROTORS
TRANSMISSION FAILURES !
Hope this doesn't burst any die hard Acura bubbles ! :( :( :( :(
Fabvsix,
You experienced steering wheel vibration in the absence of brake pedal pulsation due to warped rotors? Please explain how this is mechanically possible.
As for speed-sensitive pulsation in the brake pedal, mine was noticeable at 50mph and got really freakin' scary at 100mph as the pulsations reverberated throughout the entire vehicle and rear seat passengers were able to feel it as well.
Alignment issues are much more noticeable at the steering wheel than at the brake pedal, and vice versa for rotor warpage.
Techniks has not indicated whether there is brake pulsation at high speed to accompany the steering wheel vibration. This is an important piece to the puzzle. Its easy enough to check for either, and of course, there's no reason why techniks couldn't have both problems. |
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| teckniks |
| well the mdx is right now at the dealer getting the brakes all changed under warrenty:2: |
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| azfansinnc |
I just got my 03 back from getting the front rotors resurfaced and pads replaced. It was all done under warranty without my saying a thing except that there was a problem.
Mileage is at 16,200. |
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| cardingtr |
JUst to add info to this tread..
My MDX is now 42K, went to the dealer today, Gunn Acura in San Antonio, TX ( I don't like this dealer but the only one that took my car without appointment) to check the brakes.
Well they said the rotors are warped and they won't cover it unter warranty because:
1. Mileage
2. Brake pad is more than 50% worn
Then they start mumbling about "sometimes it's how you drive" , "it's a wear item", "it's a brake part that is a wear item"
Funny thing is I told the tech its a problem because its a very common problem with MDX. Then he told me I'm the first one. Usual answer.
He then told me its normal wear part so its expected and not covered. ???!! So I raised my voice and told him,..If it a normal wear part, its expected then why I am the first one? So he told me again about miles but then I'm less than warranty miles?? We did this for a while but I ended up paying $210 out of frustration and we are taking off for two weeks vacation.
And also my invoice said warped. Then he resurfaced it. How can you repair a warped rotor by resurfacing? Correct me if I'm wrong but you resurface something if its rough but not warped. The only way to fix a warped rotor is melt it.
I felt robbed. |
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| sidewinder |
| You definitely got robbed if all they did was resurface the roters for that much!!! If they also replaced the pads then it might make it a little better. I tried to have my 01 done but all they could do was go 50% on it so I ended up paying $50 to resurface the rotors. (and only reason they did that was because of low mileage 22K). |
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| cardingtr |
They replaced the pads and resurfaced the rotors. Maybe when they say "WARPED ROTORS" they meant rough rotors surface?
I also raised the question of resurfasing makes the rotors thinner and makes it prone to future "warping". They said it should not be affected since they basically removes dusts metals from it.
So now I have this impression that when they say warped rotors, it could only mean rough rotor surface. |
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| PsiStar |
I'll pass this link along warped rotors myth
I have the Stoptech big brake kit on a Subaru WRX /w race pads. Did the break in procedure as they and every race driver will tell you is necessary ... dramatic amount of smoke from all 4 corners initially BTW .... & the rotors get nicely coated. Result ... very smooth braking even from 140+ down to 20 or so at tire traction threshold.
Of course these not are the conditions our X's are driven in, but there is some merit to the "bedding in" process as well as "braking hard" concerns by dealers. Imagine the chaos that would be caused if all auto makers had a bedding procedure for new car deliveries not to mention the added confusion with new pad installations. The 1st questions that is raised is, "... exactly where am I going to do this & not get rear ended or attract the wrong kind of attention?!?!"
I don't think that this bedding process is necessary for the standard grocery getter. But, should you have to brake unusually hard, and certainly if the brakes have to used repeatedly hard, do not come to a complete rest with your foot planted hard on the brakes. The real excuse for letting your car creep forward at traffic stops or even pop the tranny into park for an extended stop.
my $.02 |
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| kimsta |
I had my rotors and pads replaced due to warping at 15k. I'm at 25k right now and they are warped again.:mad:
MDX rotors suck! |
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| Bnuke |
| I just completed a move from Connecticut to San Diego and I noticed the vibration developing around Kansas. I wasn't using the brakes at all. What's up with that? |
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| DaleB |
quote:
Originally posted by PsiStar
Of course these not are the conditions our X's are driven in, but there is some merit to the "bedding in" process as well as "braking hard" concerns by dealers. Imagine the chaos that would be caused if all auto makers had a bedding procedure for new car deliveries not to mention the added confusion with new pad installations. The 1st questions that is raised is, "... exactly where am I going to do this & not get rear ended or attract the wrong kind of attention?!?!"
I don't think that this bedding process is necessary for the standard grocery getter. But, should you have to brake unusually hard, and certainly if the brakes have to used repeatedly hard, do not come to a complete rest with your foot planted hard on the brakes. The real excuse for letting your car creep forward at traffic stops or even pop the tranny into park for an extended stop.
my $.02
Hardly a universal practice that is needed for every vehicle, but interesting.
I had an '82 Celica and never even thought about how I brake. I popped in new pads when they got low and drove on. It always braked smoothly. At a 106K miles, it had a brake overhaul. The first time the rotors were ever turned. Similar experience on a Mazda RX7, and that baby was driven hard. I probably usesd the 'StopTech' technique as a matter of normal driving...First turning at 65k.
Maybe the rotors were thicker, etc. I have no idea, but I don't see why it should be that different from car to car unless the driver is very abusive, or the materials vary in quality between mfrs.
Different weight class? Well, are Toyota RX, Highlander, or 4Runner owners complaining about warped rotors? If not, I think we have our answer. |
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| Dick at Incline |
| Well looks like I have the dreaded Warped Rotor Problem. My brakes have started to pulsate--21,500miles. I live in the mountains but I always gear down, when coming down hills. I bedded in the brakes as suggested, and I am careful on the brakes in the mountains. Oh well, here I go to the dealer and see what response I get. In over 40 years of driving this is the first warped rotor problem I can recall. |
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| BlueStreak |
quote:
Originally posted by RobK
JeffK,
I have to disagree with you. Well, at least partly. Design and manufacturing defects certainly can cause pulsation. However, those two things are not always the cause.
Driver behaviour can also be to blame, as does normal wear of the rotor.
What causes pulsation is thickness variation on each side of the rotor. "warping" is not really the correct term to use because the word warp tends to be understood to mean the entire rotor (ie., both surfaces) "warp" in the same direction at the same spot on the rotor. This would not cause a pulsation on a lot of vehicles because the caliper design allows the caliper to slide, and "follow" the warpage of the rotor.
What can cause thickness variation, among defects in the material itself, is heat. So for example, if a person rides their brakes hard on the way home, getting the caliper and pads good and hot, then parks the vehicle, most of the rotor is able to dissipate the heat quickly except the part that is underneath the caliper. This tends to happen more easily as a rotor wears because it gets thinner with age and therefore cannot dissipate heat as well.
By your own statement here, you seem to negate what you say about wear not being a cause of pulsation. Your statement is correct, as a rotor gets thinner (either by machining or normal wear) it is not able to dissipate heat as well as when new, and therefore more susceptible to pulsation.
So there's my $.02. In any case, it's good to argue with you again JeffK!
-Rob-
Keep in mind there are various metals in the composition of the rotor. As various metals expand and contract at different temperature intervals, they become subject to pressure as temperatures change. Thus, they can and do warp. I have found NAPA rotors are much less prone to warping than Raybestos, for example (based on my unscientific trials).
As I mentioned previously, my 1994 Accord EX sedan went 108K and the front rotors never warped and were at 80% of factory spec when I replaced them. Then I hear 96 Accord owners complainign about what MDX owners are, and the 96 and 96 Accords are the same generation/body style.
The rotors are fairly cheap, so when you're fed up with the pulsation, replace them. Still sad to see Acura cutting corners on things like this. Sure don't expect this on a 40k vehicle. |
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