525iSE

oh the groan... only happens in the morning then after (i'm guessing here) all the oils are pumped and everything, it doesn't groan again until it gets wet or cold... sorry i misunderstood you earlier...

Lomag

I had a brake squeal/noise when comming to stop and it was even worse when going in reverse. Apparently it was due to the brake sensors which my dealer replaced. The attached SIB describes this problem and it also calls for replacing the brake pads. I had all 4 sensors and pads replaced. It affects cars produced prior to 01/2006 so I don't think any MY2007's should be affected by this but you might want to have a look!

SIB_340206.pdf

525dse

My car does it. However I'm sure nearly all cars do ( all previous cars). Its nearly impossible for the car not to make the noise. My boss has a continental GT and also makes the grumble noise, 5 series is a very refined car but its still a car and will make some mechanical noise.

ImolaRedM

Never drove a BMW that had this. From my E12 530i, two E28 533i's, E34 535i, E39 540i, E36/7 M Roadster, E53 X5, and the current E60 530i. Maybe I just brake hard.

daytrader0

I just found some info. that might MonacoBMW. I talked to my cousin who's own a european repair shop that fixes BMW, Porsche, and MB. He told me that the groan come from the hydraulic brake calibers. He saids that when the car at park then you press on the brake pedal this activate the hydraulic calibers to press down on the rotor. At this point, the calibers are in cold stage which metal part can make friction noises. Once the brake system is sufficient warm up all metal parts expand to their final stages then the noise will goes away. Also, he noted that if the car has new rotors, calibers in break in period which can make the groaning noise. Only if the groaning noise is excessive at any levels of driving then you need to bring in for expert to check them out.

Finally, he adviced me to keep the brake system clean from brake dust and foreign matters, otherwise it's "NORMAL"

monacobmw

Thanks, this is good information. My groaning is excessive. The service tech drove the car and admitted that the noise was bad. I am driving an X3 loaner with 4000 miles on it, so I can tell the "normal" groan from my own car. I guess the question is why MBs do not make the same noise.

I clean the wheels every weekend. I wonder if the solvents can have a bad effect on the brakes.

Thanks again.

daytrader0

monacoBMW,

Stay away from those solvents that clean wheels/brake. These stuffs have acid base very corrosive. Bad for your wheels, brake components and worst of all eat up any metal moving parts.

amadeus00

I have experience this brake groan and I reduce this noise by conducting a series of hard braking. Find a nice streach of empty road and get your speed up to about 80mph and brake as hard as possible without triggering ABS. Do NOT come to a complete stop. Repeat twice. Remember not to come to a complete stop. This is so the brake can cool evenly.

These 5er have big stopping power so it is natural that it groans while gentle braking. My IS300 has the same problem.

Don't use solvents, they'll just wash away any lube in the external brake system which may result in clanking noises. Only use solvents when you are cleaning and repair/replacing brakes.

monacobmw

I just got my car back from the dealership.

The dealer took me into another 5-series to show me that all 5-series make the noise.

My car was making another braking noise (a whooshing noise), which the dealer attributed to rust that was building up around the hub. They cleaned the hub, and put some WD-40 on it to prevent additional rust.

Overall, the dealer was nice. I guess we all just have to get used to this issue. It is a shame that such an expensive car has this bad feature.

tomv

daytrader, did your cousin say what the mileage breakin period is for new calipers????? Please ask him if you can. I have 650 miles on my 530 and still get the rubbing, groan noise as we have all stated here. Thanks for your help.