AtWhatMileage
Model year report

2021 BMW 840I: what breaks, and at what mileage

What breaks on the 2021 BMW 840I

No owner has filed a defect report with NHTSA about the 2021 BMW 840I. That is not a clean bill of health — it usually means few were sold, or the year is too new for problems to have surfaced.

Recalls on the 2021 model year

NHTSA has issued 4 recall campaigns covering the 2021 BMW 840I, affecting an estimated 10,083 vehicles. A recall is a different kind of evidence from a complaint: it is the regulator and the manufacturer agreeing that something has to be fixed, and the fix is free for as long as the car exists.

The campaigns cover electrical system:starter assembly, back over prevention: sensing system: camera, service brakes, hydraulic and electrical system:12v/24v/48v battery. Whether the work was actually done on the car in front of you is a question only the VIN can answer, and the manufacturer or NHTSA will answer it free.

Recalls also distort complaint counts. Publicity about a campaign reminds owners that complaining is possible, so reports for a recalled component often spike after the recall rather than before it.

25V644000

ELECTRICAL SYSTEM:STARTER ASSEMBLY

145,102 vehicles 2025-09-25
Defect
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.
Consequence
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 NHTSA.gov November 17, 2025.
21V096000

BACK OVER PREVENTION: SENSING SYSTEM: CAMERA

13,858 vehicles 2021-02-19
Defect
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…
Consequence
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.
21V062000

SERVICE BRAKES, HYDRAULIC

893 vehicles 2021-02-10
Defect
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…
Consequence
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.
20V761000

ELECTRICAL SYSTEM:12V/24V/48V BATTERY

812 vehicles 2020-12-09
Defect
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.
Consequence
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 work is free at a franchised dealer regardless of the car's age. Check the VIN at nhtsa.gov/recalls before assuming it was done.

Every year of the BMW 840I

Scores compare each year against other cars of the same model year, so a low number on an older car is a real result and not an artefact of age.

Why this page is short

A model year needs about 8 reports before percentiles mean anything, and this one does not have them. Complaint volume tracks how many cars were sold and how long they have been on the road, so a thin page usually means a rare car, a new car, or a car whose owners do not file.

Where this comes from. Every figure above is computed from NHTSA owner complaints and recall records for this exact make, model and year. Complaints are voluntary and self-selected, so treat counts as a floor. The methodology page writes out each formula, and the same numbers are available as JSON.

What breaks at my mileage Compare with another car

Source Owner complaints and recall records published by the US National Highway Traffic Safety Administration, model years 1996–2027 Figures rebuilt Published by AtWhatMileage How every figure is computed