[jritt@essex]

Most of the time, brake squeal is related to not having the brake pads and discs bed-in/burnished with each other. When you heat your brakes enough, the brake pads leave a light layer of pad material on the disc face (pad transfer layer). Then the pads ride on that layer of like material, rather than on the bare iron disc face. Think of it like rubbing your hands together, rather than running your hand over something smooth. The pad material on the disc face dampens noise.
When you drive your brakes and don't heat them up much, they work in an abrasive manner. They scrape the pad material off the disc face. If you daily drive, the pad transfer layer will gradually wear off, and you need to bed them in again to lay down a fresh pad transfer layer on the disc face. Below is a video on how to do a proper bed-in, and how to swap between street and race pads. If you digest everything in these two videos, you'll be armed with enough knowledge to keep your brakes quiet and working effectively.

[Southtown]

Yeah I need to do that. At 250 miles, mine just started squealing.

[wjones14]

Originally Posted by JABCAT

I counted 6 brake pad threads on the first 2 pages of this sub-forum. I recommend the iSweep pads. I have the 1500s on both my M2 & my wife's X3MC. Virtually no dust & zero noise.

Thanks for the suggestion. I did more research reading these forums and see that iSweep is a popular choice to eliminate the noise and additionally reduce the dust.

Still seeing conflicting opinions on my particular situation, however, which is the occasional track day. What I'm reading is that most people think the popular low dust/noise options are great for daily driving, but probably should be avoided for track use.

My track use consists of one track day per year. I've been doing this since 2007 with a Mustang GT, M235i, Camaro 2SS 1LE, and now have taken my M2C to Watkins Glen and Lime Rock. I run in the Intermediate run group, no mods, and I'm not out to set any records. I consider myself a casual track guy, with the main goals of having fun and bringing it home with the shiny side up. So bottom line, I'm not driving as hard as the Advanced group, and not doing deep, hard braking into the turns. I usually start braking more toward the beginning of the braking markers rather than the end.

So I wonder what the recommendation is for a low noise pad that could hold up for a casual track day like mine once a year?

[chris719]

Originally Posted by wjones14

Thanks for the suggestion. I did more research reading these forums and see that iSweep is a popular choice to eliminate the noise and additionally reduce the dust.

Still seeing conflicting opinions on my particular situation, however, which is the occasional track day. What I'm reading is that most people think the popular low dust/noise options are great for daily driving, but probably should be avoided for track use.

My track use consists of one track day per year. I've been doing this since 2007 with a Mustang GT, M235i, Camaro 2SS 1LE, and now have taken my M2C to Watkins Glen and Lime Rock. I run in the Intermediate run group, no mods, and I'm not out to set any records. I consider myself a casual track guy, with the main goals of having fun and bringing it home with the shiny side up. So bottom line, I'm not driving as hard as the Advanced group, and not doing deep, hard braking into the turns. I usually start braking more toward the beginning of the braking markers rather than the end.

So I wonder what the recommendation is for a low noise pad that could hold up for a casual track day like mine once a year?

Probably Endless MX72 or MX72 Plus. However, whether they are quiet on these calipers is hard to say unless someone else has tried them.

[JABCAT]

Originally Posted by wjones14

Thanks for the suggestion. I did more research reading these forums and see that iSweep is a popular choice to eliminate the noise and additionally reduce the dust.

Still seeing conflicting opinions on my particular situation, however, which is the occasional track day. What I'm reading is that most people think the popular low dust/noise options are great for daily driving, but probably should be avoided for track use.

My track use consists of one track day per year. I've been doing this since 2007 with a Mustang GT, M235i, Camaro 2SS 1LE, and now have taken my M2C to Watkins Glen and Lime Rock. I run in the Intermediate run group, no mods, and I'm not out to set any records. I consider myself a casual track guy, with the main goals of having fun and bringing it home with the shiny side up. So bottom line, I'm not driving as hard as the Advanced group, and not doing deep, hard braking into the turns. I usually start braking more toward the beginning of the braking markers rather than the end.

So I wonder what the recommendation is for a low noise pad that could hold up for a casual track day like mine once a year?

If you're doing one track day per year just swap in some track pads. The pad swap takes ~20 min for all 4. It's a piece of cake.

[apez]

Originally Posted by JABCAT

If you're doing one track day per year just swap in some track pads. The pad swap takes ~20 min for all 4. It's a piece of cake.

I would love a step by step guide for this, particularly whatever you need to release the rear calipers. (My understanding is this is complicated)

You don't need to bleed breaks afterwards do you?

[JABCAT]

Originally Posted by apez

I would love a step by step guide for this, particularly whatever you need to release the rear calipers. (My understanding is this is complicated)

You don't need to bleed breaks afterwards do you?

There's a few youtube videos that show how to release the parking brake on the rear calipers. I was going to take some pics when I did it, but it was honestly so easy/quick that I forgot to snap some. You remove the parking brake actuator, open it & use a t-45 bit to retract it by turning the motor clockwise until it stops. The left front & right rear have the brake sensors, so be carful removing those as they are fragile. They can be reused. No bleeding is necessary, and engage/release the parking brake before driving as you might get a "parking brake malfunction error" initially, but doing this resets it.

[wjones14]

Originally Posted by JABCAT

If you're doing one track day per year just swap in some track pads. The pad swap takes ~20 min for all 4. It's a piece of cake.

Appreciate the advice. I was kind of hoping not to have to swap them for track days, but if that's what it takes, then so be it.

I'll believe < 20 minutes for all 4 when I see it though. I swap my winter and summer wheels every year in my garage, and that takes almost an hour. I'm sure I'm slower than most. Maybe after I did the brakes a couple times I could reduce the time, but I'm thinking it would definitely be over an hour for me.

Was hoping there was a single set of pads that could do it all without squealing, but maybe there isn't.

[JABCAT]

Originally Posted by wjones14

Appreciate the advice. I was kind of hoping not to have to swap them for track days, but if that's what it takes, then so be it.

I'll believe < 20 minutes for all 4 when I see it though. I swap my winter and summer wheels every year in my garage, and that takes almost an hour. I'm sure I'm slower than most. Maybe after I did the brakes a couple times I could reduce the time, but I'm thinking it would definitely be over an hour for me.

Was hoping there was a single set of pads that could do it all without squealing, but maybe there isn't.

Genuinely curious why it takes almost an hour to swap wheels? I use two low-profile jacks, jack up one side, break the lug bolts loose then remove them with an impact. Wheels off, new on, zip zip lug bolts and torque to spec. Less than 10 min each side.

I swapped pads on both my wife's X3MC and my M2. I did the X3 first, honestly it was maybe 20 min. The X3's fronts are easier as you don't have to remove the caliper. The pads just slide out when you remove the pins & spring clip. On the M2 you do have to remove the front caliper to remove the pads, but it's two bolts. The rears are the same on both vehicles. It's honestly the easiest pad swap I've ever done, and I've done quite a few. It definitely shouldn't take you an hour.

[baron95]

Everyone should first just try to bed in their pads correctly - google a bedding procedure from StopTech for examples and follow it.

If you are never tracking the car, then just swap the front pads which are the ones that tend to be noisy, for a ceramic, low dust street pad and you are done.

If you are tracking the car regularly, then you are likely keeping the pads well bedded in anyway.

It's not that complicated to address these issues without pulling your hair out.

[wjones14]

Originally Posted by JABCAT

Genuinely curious why it takes almost an hour to swap wheels? I use two low-profile jacks, jack up one side, break the lug bolts loose then remove them with an impact. Wheels off, new on, zip zip lug bolts and torque to spec. Less than 10 min each side.

I swapped pads on both my wife's X3MC and my M2. I did the X3 first, honestly it was maybe 20 min. The X3's fronts are easier as you don't have to remove the caliper. The pads just slide out when you remove the pins & spring clip. On the M2 you do have to remove the front caliper to remove the pads, but it's two bolts. The rears are the same on both vehicles. It's honestly the easiest pad swap I've ever done, and I've done quite a few. It definitely shouldn't take you an hour.

Well, let me count the reasons... I'm not about speed whenever I work on the car. I take my time. I don't have two jacks. I don't have an impact gun. Part of the time is spent bringing the wheels up from the basement to the garage. And bringing the wheels I just took off down to the basement. And then the time to fill the tires with air is all included in the time to swap wheels. Maybe I counted the time to drive around the block to reset the TPMS, but I was never questioned on why it took an hour. All I know is that's about what it takes.

Guaranteed with brakes I would be even more careful and methodical. At least the first time. I have swapped pads and rotors before on my 2005 Mustang, so I have a general idea of the process. It's something I'd just rather not do every time I do a track day and then have to swap back afterwards.

[wjones14]

Originally Posted by baron95

Everyone should first just try to bed in their pads correctly - google a bedding procedure from StopTech for examples and follow it.

If you are never tracking the car, then just swap the front pads which are the ones that tend to be noisy, for a ceramic, low dust street pad and you are done.

If you are tracking the car regularly, then you are likely keeping the pads well bedded in anyway.

It's not that complicated to address these issues without pulling your hair out.

Believe me, I've tried bedding them too many times to count. I actually do it regularly when the squeal becomes too loud to take. Sometimes almost weekly. Recently I did bring the car to my dealership to have them check out the brakes to see if there were any problems. The tech sprayed some SBS brake treatment on them and bedded the brakes himself. He told me that should quiet them somewhat but it won't stop the squeal 100%. It did quiet them. On the drive home I only heard them squeal at a couple stop signs.

I'm thinking some it's partly luck of the draw. I have a friend who lives nearby and had an M2C, and he said he never had a brake squeal problem and his car was a daily driver like mine. Maybe we have different driving habits? It's just super frustrating.

I had a Camaro 2SS 1LE with huge 6-piston Brembos and I never heard a peep from them in 3 years. Not one time.

[ttaidapos]

Coming from 6 piston and 4 piston brembo Alfas and Nissan, plenty of miles on all three cars, enough to change front pads. Never heard pip from either car or pads. Mine kicked in at about 900miles, very inconsistent as to when besides low speed driving in parking lots but still inconsistent. Dealer inspected everything during break in service, result... live with it.

[Southtown]

Originally Posted by wjones14

Believe me, I've tried bedding them too many times to count. I actually do it regularly when the squeal becomes too loud to take. Sometimes almost weekly. Recently I did bring the car to my dealership to have them check out the brakes to see if there were any problems. The tech sprayed some SBS brake treatment on them and bedded the brakes himself. He told me that should quiet them somewhat but it won't stop the squeal 100%. It did quiet them. On the drive home I only heard them squeal at a couple stop signs.

I'm thinking some it's partly luck of the draw. I have a friend who lives nearby and had an M2C, and he said he never had a brake squeal problem and his car was a daily driver like mine. Maybe we have different driving habits? It's just super frustrating.

I had a Camaro 2SS 1LE with huge 6-piston Brembos and I never heard a peep from them in 3 years. Not one time.

I think it’s luck as well. My sti with brembos never squeaked the 10 years I owned it. My M2 started at 200 miles and it’s pretty loud with light breaking.

[baron95]

Originally Posted by wjones14

Believe me, I've tried bedding them too many times to count. I actually do it regularly when the squeal becomes too loud to take. Sometimes almost weekly. Recently I did bring the car to my dealership to have them check out the brakes to see if there were any problems. The tech sprayed some SBS brake treatment on them and bedded the brakes himself. He told me that should quiet them somewhat but it won't stop the squeal 100%. It did quiet them. On the drive home I only heard them squeal at a couple stop signs.

I'm thinking some it's partly luck of the draw. I have a friend who lives nearby and had an M2C, and he said he never had a brake squeal problem and his car was a daily driver like mine. Maybe we have different driving habits? It's just super frustrating.

I had a Camaro 2SS 1LE with huge 6-piston Brembos and I never heard a peep from them in 3 years. Not one time.

You and me both. I had an SS1LE prior to this M2 and not a peep for the 6-pot fronts and 4-pot rear Brembos. And I have run exclusively track pads on it (multiple brands) and never, ever had any squeal. Before that I had a C7 Vette - same story - exclusively track pads not a peep. Before that a Mustang with Brembo brakes that would squeal like a MF with track pads on, but never with the OEM "track pack" pads.

These brake systems can be designed to not squeal. I'm not sure why BMW can't get it done even with the OEM pads.

[chris719]

Originally Posted by baron95

Everyone should first just try to bed in their pads correctly - google a bedding procedure from StopTech for examples and follow it.

If you are never tracking the car, then just swap the front pads which are the ones that tend to be noisy, for a ceramic, low dust street pad and you are done.

If you are tracking the car regularly, then you are likely keeping the pads well bedded in anyway.

It's not that complicated to address these issues without pulling your hair out.

The OEM pads are not designed to be bedded in and it won't help for more than a few days. The OE style friction material is primarily relying on abrasive friction not adhesive friction like aftermaket pads. This has all been tried by F10 M5 owners who had the first 6 pot BMW brakes with this noise issue. The only permanent solution is changing the pad material, but you will give up some initial bite.

Originally Posted by baron95

You and me both. I had an SS1LE prior to this M2 and not a peep for the 6-pot fronts and 4-pot rear Brembos. And I have run exclusively track pads on it (multiple brands) and never, ever had any squeal. Before that I had a C7 Vette - same story - exclusively track pads not a peep. Before that a Mustang with Brembo brakes that would squeal like a MF with track pads on, but never with the OEM "track pack" pads.

These brake systems can be designed to not squeal. I'm not sure why BMW can't get it done even with the OEM pads.

BMW has a EU compliant low-copper NAO pad formulation and they also prefer very high mu / bite so these large brakes stop in all conditions like freezing cold and wet.

[baron95]

Originally Posted by JABCAT

Genuinely curious why it takes almost an hour to swap wheels? I use two low-profile jacks, jack up one side, break the lug bolts loose then remove them with an impact. Wheels off, new on, zip zip lug bolts and torque to spec. Less than 10 min each side.

I have multiple floor jacks and all the tools I could possibly need in my garage, and I have changed brakes countless times. There is no conceivable way I can do all 4 in 20 min.

Having said that, it should be fairly easy to determine which brakes are generating the squeal front (most likely) or rears (less likely) and change just those for track. If you are doing just fronts and just doing the pads and nothing else you can do both methodically and carefully in 30-40 min.

I never change just pads though. When I change pads, I also bleed the brakes to get rid or the old brake fluid that just bakes in the caliper - this way I always have fresh fluid in - better than doing a flush once a year, so it takes me about 1 hr per axle.

[baron95]

Originally Posted by chris719

The OEM pads are not designed to be bedded in and it won't help for more than a few days. The OE style friction material is primarily relying on abrasive friction not adhesive friction like aftermaket pads. This has all been tried by F10 M5 owners who had the first 6 pot BMW brakes with this noise issue. The only permanent solution is changing the pad material, but you will give up some initial bite.

Interesting - I have 1,200 miles and no peep yet from the brakes and I'm 2 weeks away from first track day. So I will have to see how they perform after they wear off.

I did bed them in and they smelled and smoked like an SoB, so I submit that they still need to be bedded in.

If it is true that they are relying just on abrasion that is bad news and that will eat pads and rotors on track like a b@$#.

[chris719]

Originally Posted by baron95

Interesting - I have 1,200 miles and no peep yet from the brakes and I'm 2 weeks away from first track day. So I will have to see how they perform after they wear off.

I did bed them in and they smelled and smoked like an SoB, so I submit that they still need to be bedded in.

If it is true that they are relying just on abrasion that is bad news and that will eat pads and rotors on track like a b@$#.

Alll Euro OEM pads work this way and have for 30 years. They do not need to be bedded, don't benefit from it, and smoking has nothing to do with need to be bedded in. All you did is reduce the life of the pads and rotors.

[baron95]

Originally Posted by chris719

Alll Euro OEM pads work this way and have for 30 years. They do not need to be bedded, don't benefit from it, and smoking has nothing to do with need to be bedded in. All you did is reduce the life of the pads and rotors.

Humm.... the smoking and burning smell is the cooking off and out venting the gases from the resins used during pad manufacturing. I certainly don't want those gases between my pads and rotors on track.

And I'm quite sure that European manufacturers like BMW M and Porsche have brake bed-in recommended procedures in their manuals.

In any event lets see how they behave.

[chris719]

Originally Posted by baron95

Humm.... the smoking and burning smell is the cooking off and out venting the gases from the resins used during pad manufacturing. I certainly don't want those gases between my pads and rotors on track.

And I'm quite sure that European manufacturers like BMW M and Porsche have brake bed-in recommended procedures in their manuals.

In any event lets see how they behave.

Stock pads are not suitable for track use and they are smoking because you are cooking the material every time you do it. It will always smoke when you get them up to a certain temperature. There is no bed-in procedure in the manual for M cars, in fact, I believe they say to drive gently for 300 miles or something like that. These is the exact same friction material that comes on a M340i, M240i, 330i, or 230i coupe. It is a street-only pad made for high bite in all weather conditions. The pads say Brembo on the shim but the stamped lettering shows they are made by Akebono, Textar, or Pagid (same formula). You can look at the material and see it is the same as all regular BMWs except the FWD cars that use some kind of super low dust pad.

[KC87ZB]

Originally Posted by baron95

I never change just pads though. When I change pads, I also bleed the brakes to get rid or the old brake fluid that just bakes in the caliper - this way I always have fresh fluid in - better than doing a flush once a year, so it takes me about 1 hr per axle.

Should always bleed brakes/change fluid after a track day.

I personally don't know enough about the stock compound on BMW M brakes but I would assume that they are not specifically track focused since the G87 is a street car first. Knowing that, I would use a more track focused pad for track days. Swapping them doesn't take that long and you should bleed the fluid anyway.