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Discussion Starter #1
The dealer is telling me my brakes are fine, even though the outside pad on the passenger side is worn extremely uneven, with part of it rubbing the rotor.

I am going to look at the car with a tech on the lift in about 3 hours, and I want to know what the minimum specs before replacement are required on the front and rear pads and rotors. I'm going to make them show me the measurements on a caliper.
 

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HDClown said:
The dealer is telling me my brakes are fine, even though the outside pad on the passenger side is worn extremely uneven, with part of it rubbing the rotor.

I am going to look at the car with a tech on the lift in about 3 hours, and I want to know what the minimum specs before replacement are required on the front and rear pads and rotors. I'm going to make them show me the measurements on a caliper.
Try Dave Z. I think I have a private email if he is not monitoring the board. PM me if you need it.
Regards,
Jerry
 

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Hey!!!
Straight from the BMW CPO check list, brakes should not be below 5mm, front and rear. Hope this helps!!! :cheers: :flag:
 

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rodman31 said:
Hey!!!
Straight from the BMW CPO check list, brakes should not be below 5mm, front and rear. Hope this helps!!! :cheers: :flag:
That is the CPO checklist- NOT THE SERVICE LIMIT.

On a cpo inspection, a 4mm pad fails but the BMW 'maintenance' will not cover that replacement.

IIRC, the pad wear indicatior is at 2 mm... not sure what the service limit is...
 

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Discussion Starter #5
I did some searching, 2mm is pad wear indicator, but 4mm is where most dealer would probably let you talk them into replacement. New they are 14mm from what I read.

I went and looked at the pads on a lift. The tech and his team leader swear up and down that this is normal:



Told me the pad is at 11mm and that it's normal to wear uneven and the bottom to rub the rotor at all times.

I took the tech for a drive and got the front right (pictuerd above) to howl like a banshee over and over. Had to get the breaks really warmed up after about 10 miles of driving, which is omething they don't do on their brief drives. So, they are keeping the car another day.

With the time they wasted today, they could have pulled the caliper, tore it apart, cleaned it, and rebuilt it. Just taking the caliper off will give them a better look at the caliper itself and let them see if anything is out of wack. They haven't even done that yet, and this is the 3rd complaint.
 

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There's still plenty of meat left on those pads. If they are noisy, just change them, and be done with it. Check with Dave Z on pad choices.

Eric
 

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Discussion Starter #7
s62fan said:
There's still plenty of meat left on those pads. If they are noisy, just change them, and be done with it. Check with Dave Z on pad choices.

Eric
I do not debate the pad thcikness. What I debate is that they are worn VERY evenly, probably a good 3-4mm worth of uneven wearing in fact. That is not correct based on every brake system I have every seen. That's a sign of an issue with the caliper.

And this is still under maintenace, I'm not paying my own money in parts and labor when there is clearly something wrong and they are just trying to screw me.
 

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HDClown said:
I do not debate the pad thcikness. What I debate is that they are worn VERY evenly, probably a good 3-4mm worth of uneven wearing in fact. That is not correct based on every brake system I have every seen. That's a sign of an issue with the caliper.


You mean the pads are are wearing more on the bottom, than the top? It's hard to notice in your picture, but they should wear evenly. If that's the case, I would have the caliper checked out. How is the other side wearing?
 

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HDClown said:
I do not debate the pad thcikness. What I debate is that they are worn VERY evenly, probably a good 3-4mm worth of uneven wearing in fact. That is not correct based on every brake system I have every seen. That's a sign of an issue with the caliper.

And this is still under maintenace, I'm not paying my own money in parts and labor when there is clearly something wrong and they are just trying to screw me.
You should expect a little uneven wear, but that looks a little extreme to me too. If both sides are the same, then I would tend to think it is normal on this car; otherwise, I would think something on that side caliper is sticking.
Regards,
JErry
 

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HD:

I am pretty sure that new pads come with an indent at the "rotational" ends of the pads, and that the indent is only on the outer diameter of the pad. It transistions as it gets near the inside. Physically it would be impossible to wear such as that appears; but I do believe you are confusing the normal indents with uneven wear.

I have a new set of OEM pads home. I will take a pic and put it up here.

From what I remember, these pads look fine. The squeal can be removed by rebedding. See Dave Z's website for the method to rebed.

Also, the rotor thickness minimums are on the edge of the rotor. Those rotors look pretty close to new.

Joe
 

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Discussion Starter #11 (Edited)
jjc1843 said:
HD:

I am pretty sure that new pads come with an indent at the "rotational" ends of the pads, and that the indent is only on the outer diameter of the pad. It transistions as it gets near the inside. Physically it would be impossible to wear such as that appears; but I do believe you are confusing the normal indents with uneven wear.

I have a new set of OEM pads home. I will take a pic and put it up here.

From what I remember, these pads look fine. The squeal can be removed by rebedding. See Dave Z's website for the method to rebed.

Also, the rotor thickness minimums are on the edge of the rotor. Those rotors look pretty close to new.
Please post pictures of the new pads. The dealership had a set and said they would show me, but I didn't have time.

The dealership removed the caliper, took it apart, cleaned it, made the pads even, and rebuilt it. They said the noises are gone.

Something was definately "wrong", since only front right would howl, and badly. There was a considerable amount of breakdust on that wheel over the front left.

It may have been as simply as a good cleaning. I was never trying to make the dealer replace parts afterall, just acknowledge a problem and take steps to fix.

Joe
 

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Joe:

These pics should define the outer "bevel" of a new set of pads.

Let me know if this helps.

Joe
 

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The indent is there to compensate for the slight camber angle of the wheels!

I think..... someone correct me so I dont make a fool of myself anywhere else!
 

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Ahmed said:
The indent is there to compensate for the slight camber angle of the wheels!

I think..... someone correct me so I dont make a fool of myself anywhere else!


Too late! :hihi: I believe the indentation is just an easy way for the techs to do a wear inspection. someone correct me before "I" make a fool of myself :haha: Dave Z, please set us straight!
 

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Discussion Starter #15
If you look at my original picture, you will see the bad is worn uneven from top to bottom. The bottom of the pad (closest to the hub) was touching the rotor, and the top was far away from it.

The new pads are not cut in this type of fashion at all. And, correct me if I'm wrong, but brake pads are not supposed to RUB the rotor when the pedal is not being pressed down. BMW Tech's at my dealer told me it's normal, and so was the angular wear on the pad from bottom to top.

After picking up my car, the squeeling was better, but it's still there. The dealer evened the pad out and cleaned everything. I'm going to have to get on some open roads to do a bedding procedure again and see where that gets me.
 

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Joe:

I still don't see it...looks like normal indents to me. Do you have another pic? That would help...
 

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HDClown said:
And, correct me if I'm wrong, but brake pads are not supposed to RUB the rotor when the pedal is not being pressed down. BMW Tech's at my dealer told me it's normal, and so was the angular wear on the pad from bottom to top.
Yes the pads normally touch the rotor. I'm no brake expert so I can't answer for the wear pattern. My guess is the pads (or piston) may have been sticking. This could cause uneven wear and noise. Now with them cleaned, a good bedding in process may help. If the pad wear is far from normal, they may need replaced.
 

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I just installed 4 new axxis deluxe brake pads and I noticed that both front pads also don't sit flat on the rotors. Since new pads have an angled edge this explains the view on your picture. So it is perfectly normal until the edges wear out and the whole pad sits on the rotor completely.

HDclown: Is this your same conclusion?
 

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There is definetly a lot of meat left on those pads, although the un - even wear just does not seem correct?
 

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Discussion Starter #20
Old thread eh. The uneven wear I had was simply NOT normal. I personally inspected the pads on the driver side of the car and they were worn much more even, and the bottom of the pad was not touching like this passenger side one was.

The dealer said they ground down the pad to have a more even surfance. Whatever they did definately help with the squeeling I was having. But now, in cold weather (which didn't happen until January here in FL), I get this weird toy horn type sound from the brakes.

I'm over it at this point, I'm going to put in aftermarket pads most likely and call it the day.
 
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