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Greetings everyone

This past weekend, when replacing the brake pads and discs on my 2018 F30, I discovered that someone had been tampering with the nuts that attach the two sides of the calliper. It appears that they had some difficulty with it, since the paint has been peeled off the heads. I had it checked out by a main dealer and an independent to make sure the bolts were torqued properly. They claim these bolts should not be removed and that the unit is sealed, thus neither of them would touch it. They would only be of use if I replaced the entire calliper, which I am obviously not interested in doing because of how much it would cost. Because you can't buy the bolts separately, they have no idea what size the calliper unit is. The independent specialist advised me to get some aftermarket ones and change them myself if he were in my shoes.


May I ask if anyone has the dimensions of these bolts and the recommended torque for them? BMW seems to think they might be E9 torx, but he isn't sure; he also mentioned that I'll need to know the thread size.I need reassurance because I'm worried about whether or not these bolts are torqued correctly. As an aside, that's the rear calliper.

You have my gratitude. Can you recommend a place where I can get OEM bolts, or will I have to settle for aftermarket ones?

See whether this website can be of assistance by contacting them.

Instead than worrying about replacing the bolts, I would simply double-check that they are snug and move forward.
Assuming they are M8 bolts, I would just tighten them to 25 nm using a torque wrench. I would go with 35 nanometres unless the grade 10.9 mark is visible.

Instead than worrying about replacing the bolts, I would simply double-check that they are snug and move forward.
Assuming they are M8 bolts, I would just tighten them to 25 nm using a torque wrench. I would go with 35 nanometres unless the grade 10.9 mark is visible.

Your assistance is greatly appreciated, my friend. I sought a second opinion at a nearby garage, and the mechanic confirmed that the bolts were torx 10. After applying 40 NM of torque, he assured me that everything was alright and reiterated your advice to "just leave them alone" for the time being. My local primary dealer was really unhelpful, though. I seriously doubt they ever glanced at it; they simply weren't interested in assisting me in the slightest. He insisted it was torx 9, which, as far as I can determine, doesn't even exist! Please, just make sure the bolts are tight and the brake fluid won't leak. That's all I wanted.

Do as instructed for the refit if they were previously problem-free.
While they are off, you can even re-paint them.

It makes me happy that you were able to receive some positive news in the end.
I can understand why the big dealer and the independent specialist would want to avoid dealing with it. Changing the complete calliper is the safest bet because it is not a functional piece. Experts in the field disassemble and reassemble callipers, and afterward, they often stamp their name on the finished product.