zibby43

Hey guys, quick question . . .

I have had my C43 for about a week now. Love the car so far.

At very low speeds, when applying the brakes fully (not gradually) to park, I hear this mild groaning sound from the brakes. It sounds a bit like a wooden stool getting pushed across a wooden floor.

It's a lower frequency sound; not a screech, whine, or high-pitched squeal. I don't hear the noise when braking from higher speeds. There are no other brake noises whatsoever. Brakes feel alright, performance-wise. Strong initial pedal feel.

I'm hoping this is normal. I believe my C63's brakes, which were perfect for 5 years, made a similar noise under the same circumstances. It's just that I'm hyper-aware of any and all new sounds/sensations since the C43 platform is new to me. My rotors are pretty dusty right now since I'm still fully bedding the brakes in.

Any and all feedback/questions welcome.

unr1

zibby43

mo11

If you’re in sport+, just switch to sport or comfort when parking. That’s what I do to avoid those normal (for this car) brake noises when I park.

zibby43

Hungalow

As mentioned above being in s+ raises the rpm a bit which can cause the brake chatter in the last sec before coming to complete stop. Being in comfort it can also happen dependant on your brake pedal application.
I wouldnt worry....

zibby43

Good point. Many thanks for the feedback!

FirstMBAMG

NYC365

Know exactly what you're talking about! I have been driving a C450 (C43 essentially) since 2016 and that noise has never went away under the same circumstances that you described. I had the brakes checked many times as mine ADDITIONALLY squealed and squeaked since my test drive in the damn car. Front needed replacing @ 6.5k miles, and rears at 17k miles. My car definitely had factory defect with brakes since they needed replacing that early, but nonetheless, the squeaking went away but the sound you described never went away even with replacing so I figured it was/is normal.

RichardCranium3

80-90% brake pressure (just shy of ABS engagement) stops at increasing/decreasing speeds from 20mph to 60mph in 10mph increments, then back down. (20, 30, 40, 50, 60, 50, 40, 30, 20mph).

zibby43

Here's a procedure I like from StopTech (used a modified version on my '13 C63 when I first got it):

For a typical performance brake system using street-performance pads, a series of ten partial braking events, from 60mph down to 10mph, will typically raise the temperature of the brake components sufficiently to be considered one bed-in set. Each of the ten partial braking events should achieve moderate-to-high deceleration (about 80 to 90% of the deceleration required to lock up the brakes and/or to engage the ABS), and they should be made one after the other, without allowing the brakes to cool in between.

Depending on the make-up of the pad material, the brake friction will seem to gain slightly in performance, and will then lose or fade somewhat by around the fifth stop (also about the time that a friction smell will be detectable in the passenger compartment). This does not indicate that the brakes are bedded-in. This phenomenon is known as a green fade, as it is characteristic of immature or ‘green' pads, in which the resins still need to be driven out of the pad material, at the point where the pads meet the rotors. In this circumstance, the upper temperature limit of the friction material will not yet have been reached.As when bedding-in any set of brakes, care should be taken regarding the longer stopping distance necessary with incompletely bedded pads.

This first set of stops in the bed-in process is only complete when all ten stops have been performed - not before. The system should then be allowed to cool, by driving the vehicle at the highest safe speed for the circumstances, without bringing it to a complete stop with the brakes still applied. After cooling the vehicle, a second set of ten partial braking events should be performed, followed by another cooling exercise. In some situations, a third set is beneficial, but two are normally sufficient.

http://www.stoptech.com/technical-su...-system-bed-in

Very, very helpful information my friend. Thanks for taking the time to share.

Super solid bed-in procedure! I like this even better than the StopTech procedure I posted above. This is more similar to the modified approach I use.

I always take it a bit easier when I'm bedding in street pads vs. race pads.

The main reason why: temperatures. The main thing I want to avoid doing with OEM street pads/rotors is glazing.

munis

Do we have aftermarket pads for this car yet? Getting sick and tired of cleaning the dust now that my VFF107 comes with a bazillion spokes literally.

zibby43

Great question.

My car is actually in the shop right now getting all 4 rotors and pads replaced under warranty. Car is only 11 days old with less than 500 miles. The original rotors were caked with black and orange rust that took almost 200 miles of heavy braking to eliminate.

Once the rust was mostly eliminated, which just happened recently, I noticed that the rear rotors had developed some ridges (and potential grooving) from uneven wear and/or potential hotspots. The excessive rust, in conjunction with the noises and vibrations I was feeling, led to a successful warranty claim.

I'm hoping to have the car back today and if so, I'll probably start a thread detailing my journey. I'm hoping it could help future buyers know what to look for when it comes to rotors that have been sitting on the lot in a warm/humid climate for a few months.