The worst 2021 BMW 840I problems
Ranked by number of owner complaints. Mileage and cost come from what owners wrote.
Problems by type
Tap a problem to see which part fails, at what mileage and in which other years.
Recalls 5
Power train: driveline: driveshaft
- What is wrong
- BMW of North America, LLC (BMW) is recalling certain 2020-2026 840i, 840i xDrive, 2021-2023 540i, 540i xDrive, M550i xDrive, and 2024-2026 750e xDrive vehicles. The connection between the driveshaft and the rear differential may become damaged, possibly resulting in a loss of power to the rear wheels or a vehicle rollaway.
- Risk
- An unexpected loss of drive power can increase the risk of a crash. In addition, a damaged driveshaft can result in a vehicle rollaway if the parking brake is not applied, increasing the risk of a crash or injury.
- Remedy
- Dealers will inspect the connection between the driveshaft and rear axle differential, and apply adhesive or replace the driveshaft and rear axle differential, as necessary, free of charge. Owner notification letters were mailed October 8, 2026. Owners may contact BMW customer service at 1‑800‑525‑7417. Vehicle Identification Numbers (VINs) involved in this recall will become searchable on beginning October 2, 2026.
Recall number 26V525000 · Recall details
Electrical system: starter assembly
- What is wrong
- BMW of North America, LLC (BMW) is recalling certain 2020 340I, X6, 2020-2025 840I, 2020-2022 740LI, 2019-2020 X7, and X5 vehicles. After repeated attempts, the starter motor may overheat from an electrical overload.
- Risk
- An overheated starter motor can ignite nearby combustible material in the engine compartment, increasing the risk of a fire.
- Remedy
- Dealers will replace the engine starter, free of charge. This recall includes vehicles repaired under recall 24V576 and those owners will need to have their vehicle repaired again. Owner notification letters were mailed February 9, 2026. Owners may contact BMW customer service at 1‑800‑525‑7417. Vehicle Identification Numbers (VINs) involved in this recall became searchable on November 17, 2025.
Recall number 25V644000 · Recall details
Back over prevention: software
- What is wrong
- BMW of North America, LLC (BMW) is recalling certain 2019-2021 X3 sDrive30i, X3 xDrive30i, X3 M40i, X3M, X4 xDrive30i, X4 M40i, M550i, X4M, X5 sDrive40i, X5 xDrive40i, X5 xDrive50i, X5M, X5 M50i, X7 xDrive40i, X7 xDrive50i, X7 M50i, Alpina XB7, 330i, 330i xDrive, M340i, M340i xDrive, and 8 Series Coupe, Convertible and Grand Coupe, 840i, 840i xDrive, M850i xDrive, M8, 2020-2021 530e, 530e xDrive, 330e, 330e xDrive, 745Le, 745Le xDrive, X5 xDrive45e, X3 xDrive30e, X6 sDrive40i, X6 xDrive40i, X6 xDrive50i, X6 M50i, X6M, 530i, 530i xDrive, 540i, 540i xDrive, M550i xDrive, M5, 740i, 740Li, 740Li xDrive, M760i Drive, M760Li xDrive, 750Li xDrive Alpina, Alpina B7 xDrive, and 2021 4 Series Coupe 430i, 430i xDrive, M440i xDrive vehicles. When shifting into Reverse, a small portion of the rearview image may be obscured, or the screen may not illuminate. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 111, "Rear Visibility."
- Risk
- If the driver relies on only the rearview camera image, the missing or reduced rearview image view can increase the risk of a crash or injury.
- Remedy
- BMW will notify owners, and dealers will inspect the rearview camera software and update it if necessary, free of charge. The recall began April 16, 2021. Owners may contact BMW customer service at 1‑800‑525‑7417.
Recall number 21V096000 · Recall details
Service brakes, hydraulic: power assist: hydraulic
- What is wrong
- BMW of North America, LLC (BMW) is recalling certain 2020-2021 8 Series Coupe, Grand Coupe and convertible 840i, 840i xDrive, M850i xDrive, M8 and 740 Li, 740 Li xDrive, 750 Li xDrive, M760 Li xDrive, X6 sDrive40i, X6 xDrive40i, X6 xdrive50i, X6 M50i, X6M, and 2019-2021 X5 sDrive40i, X5 xDrive40i, X5 xDrive50i, X5 M50i, X5M, X7 xDrive40i, X7 xDrive50i, X7 M50i, and 2021 M3, M3 Competition, M4 Coupe, M4 Competition Coupe, X5 xDrive45e, 745 Le xDrive. The rotor and shaft within the integrated brake system may not have been welded properly and could separate during a hard braking event, possibly resulting in a loss of the Antilock Brake System (ABS) and braking assistance.
- Risk
- A loss of ABS and a reduction in braking assistance can increase the risk of a crash.
- Remedy
- BMW will notify owners, and dealers will replace the integrated brake system, free of charge. Owner notification letters were mailed on May 25, 2021. Owners may contact BMW customer service at 1‑800‑525‑7417.
Recall number 21V062000 · Recall details
Electrical system: 12v/24v/48v battery
- What is wrong
- BMW of North America, LLC (BMW) is recalling certain 2021 M340i xDrive, M440i xDrive Coupe, 530i, 530i xDrive, 540i, 540i xDrive, 740Li, 740Li xDrive, 840i Gran Coupe, 840i xDrive Gran Coupe, X5 sDrive40i, X5 xDrive40i, X6 sDrive40i, X6 xDrive40i, and X7 xDrive40i vehicles. The connection between the 48-Volt battery and the starter-generator may not have been assembled properly, which can cause increased electrical resistance at the connections.
- Risk
- Increased electrical resistance can increase the risk of a fire.
- Remedy
- BMW will notify owners, and dealers will inspect the connection between the 48-Volt battery and the starter-generator assembly, replacing it if necessary, free of charge. The recall is expected to begin April 12, 2021. Owners may contact BMW customer service at 1‑800‑525‑7417.
Recall number 20V761000 · Recall details
Technical service bulletins for the 2021 BMW 840I 125
Bulletins tell dealers how to fix known problems. A warranty extension means the manufacturer pays for that repair for longer.
- The EVAP systems purge (vent) valve limited warranty for defects in materials and / or workmanship has...
- The manual starting of electronic engine oil level measurement from inside the vehicle, usually...
- If the seat ventilation is deactivated via the switch or due to parking the vehicle, the fans in the seat...
- The basic conditions for initializing the power windows are not met.
- The electrical system of BMW vehicles has been subject to an ongoing development process over the last few...
- At low outside temperatures (below 40 degrees F) and slow driving speeds (i.e. when parking,...
- A vehicle arrives at your center to be diagnosed for a micro-leak in the fuel evaporative (EVAP)...
- The Central Information Display goes black intermittently due to resets of the Head Unit (HU-H3)....
- Situation
- Customer states one of the front seats is inoperative
Compare the 2021 BMW 840I
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Questions about the 2021 BMW 840I
Is the 2021 BMW 840I reliable?
Owners have filed 0 complaints about the 2021 BMW 840I.
What is the most common problem with the 2021 BMW 840I?
There are not enough complaints to tell.
How many recalls does the 2021 BMW 840I have?
5 recalls, covering power train, electrical system and back over prevention.
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