# Service bulletin B340921

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 10233158
- Published by NHTSA: 2023\-03\-20
- Manufacturer's number: B340921
- Manufacturer's date: 2023\-02\-01
- NHTSA component: SERVICE BRAKES

## NHTSA's summary

A turbine\-like noise can be heard from the rear axle while deceleration during the first 300 miles of operation when braking from low speed.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2023/MC-10233158-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2023/MC-10233158-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Brakes

## Vehicles listed

- 2016 to 2022 BMW M2
- 2015 to 2018 BMW M3
- 2021 to 2022 BMW M3
- 2015 to 2022 BMW M4

## Recalls for the same vehicles and component

- [21V062000](/recalls/nhtsa/21V062000.md), 2021-02-10: SERVICE BRAKES, HYDRAULIC:POWER ASSIST:HYDRAULIC; SERVICE BRAKES, HYDRAULIC

## Other bulletins for the same vehicles and component

- [B064725](/bulletins/11024227.md), 2025-10-10, Other: SERVICE BRAKES. Protection Plate Return
- [B340921](/bulletins/11013041.md), 2025-01-23, Service bulletin: SERVICE BRAKES. A turbine\-like noise can be heard from the rear axle while deceleration during the first 300 miles of operation when braking from low speed.
- [B340714](/bulletins/10244237.md), 2023-11-01, Service bulletin: SERVICE BRAKES, HYDRAULIC. Functional noises \(squealing/honking\) when braking shortly before the vehicle comes to a stop. CAUSE Material\-
- [B360122](/bulletins/10211855.md), 2022-05-16, Service bulletin: SERVICE BRAKES, HYDRAULIC; WHEELS; TIRES:PRESSURE MONITORING AND REGULATING SYSTEMS. After replacing tires and successfully programming the Tire Pressure Monitoring System \(TPMS\) using the RDC tool to transfer the QR code information on the sidewall, the "back\-end" support systems need time to update the new tire information.
- [SIB340721](/bulletins/10204625.md), 2021-12-13, Service bulletin: SERVICE BRAKES, HYDRAULIC:POWER ASSIST:HYDRAULIC. When starting the vehicle vehicle at standstill, various yellow Check Control Messages CCMs appear. ID code 00042: Brake system. Additional notes: Avoid abrupt braking as far as possible. Drive at a moderate speed. Have it checked by your nearest Service Center. ID code 2046: Braking force assistance. Additional notes: Braking force assistance failure. Higher pedal force required for vehicle deceleration. Drive at a moderate speed. Have it checked by your nearest Service Center.
- [B341019](/bulletins/10203336.md), 2021-11-08, Service bulletin: SERVICE BRAKES, HYDRAULIC. Inform the customer during a consultation that the M Compound \(standard equipment\) and M Carbon Ceramic \(optional\) brakes are high\-performance brake systems which are designed for sporty, dynamic driving styles. As a side effect of the highest possible brake performance, customers are likely to hear noises due to the extremely resilient materials. In the same conversation, inform the customer that his/her braking performance can help ensure that the noises do not occur or disappear quickly.
- [B341019](/bulletins/10201141.md), 2021-09-07, Service bulletin: SERVICE BRAKES, HYDRAULIC. Inform the customer during a consultation that the M Compound \(standard equipment\) and M Carbon Ceramic \(optional\) brakes are high\-performance brake systems which are designed for sporty, dynamic driving styles. As a side effect of the highest possible brake performance, customers are likely to hear noises due to the extremely resilient materials In the same conversation, inform the customer that his/her braking performance can help ensure that the noises do not occur or disappear quickly.
- [B511121](/bulletins/10198904.md), 2021-07-06, Service bulletin: PARKING BRAKE. ROOF TRIM STRIP LOOSE AT REAR: The roof trim strip may be loose at the last \(rearmost\) clip as shown. This can occur on either side of the roof, or on both sides.
- [B360121](/bulletins/10194298.md), 2021-05-24, Service bulletin: EQUIPMENT ADAPTIVE/MOBILITY; EQUIPMENT; SERVICE BRAKES, AIR:DISC. Diagnosis of Compound Brake System Complaints in M Vehicles: 1. Visible cracks are caused by high thermal stresses during rapid heating and cooling of the brake discs. Braking from high speed with cold brake components \(less than 212 degrees F\) increases the likelihood of cracks to form.
- [B340414](/bulletins/10194296.md), 2021-05-24, Service bulletin: SERVICE BRAKES, AIR:DISC; STEERING: STEERING WHEEL/HANDLE BAR. Diagnosis of Compound Brake System Complaints in M Vehicles: 1. Visible cracks are caused by high thermal stresses during rapid heating and cooling of the brake discs. Braking from high speed with cold brake components \(less than 212 degrees F\) increases the likelihood of cracks to form.

JSON: [/v1/bulletins/10233158](/v1/bulletins/10233158)

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