2011 M3 brake issue

[stujelly]

Anyone out there having issues with their factory brakes. I have 9200 miles on my car with the double clutch auto. I am on my second set of rotors and I am having the same problem again. I am getting bad break modulation like the rotors are warped, again. I suspect it is because the E brake gets used as a back up. I think the rotors are getting hot and then I park using the e brake.

Anyone having a similar issue or recommend a fix. No track use, just street for regular everyday use.

Thanks

[ThunderMoose]

I am pretty sure that our e-brake is a drum style brake on the inner hub of the rotor so it should not be causing your rotors to warp.

Are you 100% sure your first set was warped? or did the service guys just go ahead and replace them? From everything I've read, 99% of "warped rotors" are really just uneven brake pad deposit. Try hitting the rotors with a hose the night before and then doing a series of hard stops the next morning when pads are cold and abrasive -- i.e. get up to 60 and then hard on brakes - repeat 6-10 times and then follow-up with some moderate to light braking to properly transfer pad material.

Some of the more knowledgeable forum members may give you some better suggestions.

[///M Ryder]

Why are you using the e-brake in a DCT car? And as stated above, try to work the pads and rotors after they have rusted over a little..........Phil

[Echo M3]

Originally Posted by stujelly

Anyone out there having issues with their factory brakes. I have 9200 miles on my car with the double clutch auto. I am on my second set of rotors and I am having the same problem again. I am getting bad break modulation like the rotors are warped, again. I suspect it is because the E brake gets used as a back up. I think the rotors are getting hot and then I park using the e brake.

Anyone having a similar issue or recommend a fix. No track use, just street for regular everyday use.

Thanks

Using the E-brake should not warp your rotors with the E9x M3. As far as I understand, the E-brake uses brake shoes, not the actual calipers, to hold the car in place. So, the only way it could theoretically warp the rotor is if you are superheating them (drifting, track use) and then leaving the parking brake up.

What is your driving style like? Do you ride the brakes a lot? It seems crazy that you're on a second set of rotors at just 9k miles without ANY track use.

[Echo M3]

Originally Posted by ThunderMoose

I am pretty sure that our e-brake is a drum style brake on the inner hub of the rotor so it should not be causing your rotors to warp.

Are you 100% sure your first set was warped? or did the service guys just go ahead and replace them? From everything I've read, 99% of "warped rotors" are really just uneven brake pad deposit. Try hitting the rotors with a hose the night before and then doing a series of hard stops the next morning when pads are cold and abrasive -- i.e. get up to 60 and then hard on brakes - repeat 6-10 times and then follow-up with some moderate to light braking to properly transfer pad material.

Some of the more knowledgeable forum members may give you some better suggestions.

I was just going to mention that. It's a possibility that the OP's rotors simply have pad deposition, which is very different from a warped rotor.

[w00tw00t]

I agree - I bet its pad deposit and not warped rotors. I've seen the parking brake shoe first hand and its a drum type system on the rear rotor. Also the parking brake doesn't automatically engage (as a backup) as per OP's statement - it is purely manually pull parking brake handle and cable operated...

[SchnellM3]

Originally Posted by ///M Ryder

Why are you using the e-brake in a DCT car?

I use it all the time.....

[///M Ryder]

Originally Posted by SchnellM3

I use it all the time.....

I think the only time I use it is when I get my mail out of the mailbox. I can understand occasional use, but I guess OP made it seem excessive.........Phil

[DylanMckay]

There is no need to use the E-brake with DCT as once you turn the car off, it goes into park mode. So unless you are on a hill or other surface where you need added security, it is not only pointless but potentially harmful if your brakes are super hot and you apply it.

[klammer]

I can't imagine the brakes ever getting hot enough on the street for the e-brake issue to come up. I mean, it's not like your doing a ton of high speed heavy braking even in canyon carving or on back roads, should only be an issue on track and yes, I use my e-brake every time.

[stujelly]

I do tend to drive the car hard around town so I know the brakes get hot. Point of clarification I apply the E brake, not automatic, but I do it every time since have bought the car. I did bed the brakes when the dealer replaced my last set of rotors and pads. I just asked them to look at them and they said they were warped and I do not ride my brakes.

Just seems odd that I am having these issues.

[spdy330]

I use my e-brake all the time by habit and have not have any issues with any of my vehicles in my 24 years of driving.

[roastbeef]

did you seat your pads into the rotors when you got your car back?

[Merlosso]

Originally Posted by DylanMckay

There is no need to use the E-brake with DCT as once you turn the car off, it goes into park mode. So unless you are on a hill or other surface where you need added security, it is not only pointless but potentially harmful if your brakes are super hot and you apply it.

Not using the e-brake puts the weight of the car on the transmission. Have you ever parked on a slight hill, shut off the car, took your foot off the brake and felt the car rock forward a little? That's the weight of the car going from the brakes to your transmission. Sure, you're in "park mode" and the car won't roll away but I would rather put the strain on the e-brake first and my transmission second.

And as others said, the e-brake is inside the rear rotor (drum style) and there's no reason to believe it would cause damage.

[stujelly]

Guys all good info and I appreciate it. Yes I did bed the brakes. I will try the upper procedure and see if that works.

I noticed nobody suggested a brembo or other replacement brake option which is a relief as I want to install an Akra exhaust in the near future and would like to use the money there.

Thanks again

[bigjae1976]

Is it a vibration? Or a soft pedal?

[thedrknows]

I get the same sound on my front right brake after one lap of the Nurburgring. After about 5 minutes off the track its gone. Sounds like the same thing you are getting. I plan on changing pads, lines, and fluid before this summer to see if it changes anything.

[stujelly]

Originally Posted by bigjae1976

Is it a vibration? Or a soft pedal?

It is a vibration on moderate backing say 60 to 25 mph.

Clearly a brake issue, vibration is not there with acceleration or decel without brakes.

I have had other vehicles with warped rotors from driving in the snow, but no snow in this case.

[HP Autosport]

Originally Posted by stujelly

Anyone out there having issues with their factory brakes. I have 9200 miles on my car with the double clutch auto. I am on my second set of rotors and I am having the same problem again. I am getting bad break modulation like the rotors are warped, again. I suspect it is because the E brake gets used as a back up. I think the rotors are getting hot and then I park using the e brake.

Anyone having a similar issue or recommend a fix. No track use, just street for regular everyday use.

Thanks

If you use your e-brake while the rear rotors are hot, regardless of design, you will warp the discs or cause your e-brakes shoes to be bond to the e-brake drum surface.

Bed in your brakes properly will also eliminate some of the judder you are experiencing.

[HP Autosport]

Originally Posted by SchnellM3

I use it all the time.....

It is a good idea to use the e-brake at all times especially on a hill as the parking paw is usually a flimsy metal lever inside of the transmission that wasn't designed to hold a vehicle in the first place.