OT: BMW replaced my quiet brakes, new ones are not

Likes2ridefar · #1 04-17-2019, 08:32 AM

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Hawker · #2 04-17-2019, 08:35 AM

I'm betting that some folks on the BMW forum have experienced the same thing at some point. Perhaps if you visited or posted there you could get some advice?

There seems to be an Owners Forum for every kind of car these days and they are a wealth of information. Good luck.

zap · #3 04-17-2019, 08:48 AM

As posted above, check out bimmer forums. Also talk to your local BMW indy shops.

Side note. My bil had a 135 and at 40k miles had front disc brakes replaced. The new discs warped within 1K and he took it back and new rotors were installed.

loxx0050 · #4 04-17-2019, 08:48 AM

Ask what material the pads are made of. If they are a ceramic type then you'll never fully get rid of the noise. But that material does provide superior braking performance as the initial bite is much better...the sacrifice being is they chew through rotors much faster than traditional softer (aka quieter) pad materials.

Also a true break-in for new pads is to do hard braking without coming to a complete stop a few times to get the pads worn down to an even surface. If the wear on the pads is uneven you'll get vibrations and noise. Recommended (as least what I've seen other car enthusiasts says) is to do several 50-60mph to 5-10mph slowdowns hard without coming to a complete stop. Usually not possible for me when changing pads to find these stretches of road that is close to do hard braking efforts at high speed but as an alternative I've done them at 30-40mph which has worked pretty well for me.

Using that brake goop on the back of the pads that make contact with the calipers helps a bit with noise too. It acts like a vibration dampener (like a ones for tennis racquet strings) to help reduce noise too. A lot of times OEM pads have some built in material for vibration dampening but it isn't always enough though.

texbike · #5 04-17-2019, 08:48 AM

Live with it? Heck no! More than likely it really is the pad compound/material as the dealer mentioned. Pads can have a MASSIVE difference from one material and compound to another in the amount of noise and dust they produce as well as braking efficacy. As mentioned previously, I would do a search on Google for pad suggestions for your specific car. That search should take you to a multitude of different forums and discussions on pad choices. At that point, I guess it comes down to a decision whether to insist that the dealer replace the pads/rotors or just pay out of your own pocket for the change.

Good luck - noisy brakes are annoying on daily drivers.

Texbike

Ralph · #6 04-17-2019, 08:51 AM

Lug nuts torqued evenly?

GScot · #7 04-17-2019, 08:56 AM

I've been through two compounds on our S5. One squeals under light braking pressure and the other made a grinding sounds. I did a complete bedding procedure after the last pad swap and it helped for a while. My wife usually drives the car but both of us usually downshift for braking and being AWD and high compression it slows down well with that. Brakes get just a bit of use at the intersection. A few trips of that and they squeal like crazy. Head of town and stop hard a few times is the solution for this car, usually lasts at least one tank of gas.

coreyaugustus · #8 04-17-2019, 08:56 AM

I like bimmerforums and e46fanatics. Both are active and helpful.
- Extra lube compound on the back of the pads is where I'd start.
- I usually do my own brakes and always had good luck with Akebono ceramic pads for keeping things quiet and less dusty.

fmradio516 · #9 04-17-2019, 09:05 AM

if its not a high pitch squeal, then its probably not the caliper to brake backing surface, so using the paste on the back of the pads probably wont help. Sounds like its a pad/rotor material or break in "issue".

Disc brakes are finicky sometimes. When I had my E30, I would change the brakes on them myself and take them out to brake them in. As soon as they got warm, they would squeal even though I used the anti squeal paste. I had to go home, jack up the car, take the brakes apart again and apply more paste until it stopped. I think one brake change, I had to do this 2-3 times.

and let me tell you, my bike disc brakes are no picnic either. they constantly made noise(BB7 non-organic pads) new rotors. I figured I heated them up too much when I broke them in as I was going down a huge hill to make brake in quicker. I replaced the pads and rotors and did the recommended speed up-slow down brake in procedure and they STILL squeal!

lhuerta · #10 04-17-2019, 09:11 AM

OP, what u r experiencing is not normal. Definitely take it back and get it done right. Talk to SA and schedule a test drive with technician...with both of you in car. I had rotors and pads replaced on all corners of my 328 about 3,000 miles ago and have not experienced what you describe. Also, post on bimmerfest and bimmerpost (seek forums specific to your model) to see if others have experienced anything similar.

Ken Robb · #11 04-17-2019, 09:37 AM

Or trade for a Honda.

I have lots of BMW experience in my history and all the comments about pads jibe with my experience. When I was doing 20+ track days a year that meant about 10 sets of pads and 5+ sets of rotors. There's no sense in me recommending specific components because new compounds are always being developed but in the mid-1990s "identical" stock BMW pads with the same part number performed very differently depending on what company manufactured them. Pagid and ATE were two that I remember and I learned to open the boxes to determine which company made the pads therein.

Gummee · #12 04-17-2019, 09:39 AM

Quote:

Originally Posted by GScot

I've been through two compounds on our S5. One squeals under light braking pressure and the other made a grinding sounds. I did a complete bedding procedure after the last pad swap and it helped for a while. My wife usually drives the car but both of us usually downshift for braking and being AWD and high compression it slows down well with that. Brakes get just a bit of use at the intersection. A few trips of that and they squeal like crazy. Head of town and stop hard a few times is the solution for this car, usually lasts at least one tank of gas.

I've always figured that brakes are cheaper to replace than clutches or gearboxes, so I don't downshift unless I'm driving 'spiritedly.'

YMMV

M

goonster · #13 04-17-2019, 10:07 AM

There is often a tradeoff between noise and dust.

You can always get quieter pads, but they may be be dustier . . .

mktng · #14 04-17-2019, 10:10 AM

Anyone who says "this is how it is. do this to help it" is just being suckered into excuses. No squealing should be heard. Especially with standard oem replacements. We're not driving race cars with crazy carbon ceramic brakes.

My dad's old 01 740i went through numerous brake replacements. Never had issues with oem replacements.

Maybe they didnt replace the hardware. Or maybe they didnt grease certain spots properly? I would have the service manager put in writing what they told you. Forward that to corporate.

loxx0050 · #15 04-17-2019, 10:18 AM

Quote:

Originally Posted by Gummee

I've always figured that brakes are cheaper to replace than clutches or gearboxes, so I don't downshift unless I'm driving 'spiritedly.'

YMMV

M

Except if you are driving in the mountains downhill you best downshift or else you're gonna have brakes that are on fire...literally.

First time I ever changed my own brake pads on one car I had a long time ago I didn't get the rear pads seated properly. They dragged and I saw smoke coming out of my rear rotor/wheel on a short drive to work (less than 5 miles but hopped on the highway for a couple of miles). Got home by driving side roads to keep the temps down and fixed that immediately once I got home (had to wait an hour for things to cool down before I could work on it though).