2021 BMW 840i xDrive Convertible
Fuel Economy Overview
The 2021 BMW 840i xDrive Convertible achieves an EPA-estimated 23 MPG in combined city and highway driving, with 20 MPG in the city and 27 MPG on the highway. Powered by a 3L 6-cylinder turbocharged engine paired with a automatic (s8), this subcompact cars features All-Wheel Drive drive.
In terms of environmental impact, the 2021 840i xDrive Convertible produces approximately 387 grams of CO2 per mile. This figure is measured under standardized EPA test conditions and represents tailpipe emissions only. For context, the average new vehicle sold in the United States produces approximately 400 grams of CO2 per mile, meaning this 840i xDrive Convertible performs better than the national average in this regard.
The estimated annual fuel cost for this vehicle is $3,000, based on 15,000 miles of driving per year and current national average fuel prices. Compared to the average new vehicle, you would save $4,250 over a 5-year period. This calculation accounts for differences in fuel consumption efficiency and provides a practical measure of long-term ownership costs attributable to fuel economy.
Energy DNA
Green Scorecard
Personalized Commute CalculatorEPA defaults to 55% City / 45% Hwy
Adjust the slider to match your daily driving habits. City driving involves stop-and-go traffic under 45mph, while highway driving represents sustained speeds over 55mph.
Aerodynamic Speed Penalty
EPA highway tests average roughly 48 mph. Driving at 75 mph increases aerodynamic drag exponentially. Expect your real-world highway fuel economy to drop by roughly 15-20% at interstate speeds.
5-Year Total Cost of Ownership
Recall Intelligence
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 & Remedy
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.
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.
Consequence & Remedy
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.
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."
Consequence & Remedy
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.
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 & Remedy
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.
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Looking for comprehensive historical data?
NHTSA FARS (Fatal Crash History) and broader generational safety trends are aggregated at the model level rather than by specific engine configurations. View the complete historical data profile for all BMW 840i xDrive Convertible configurations.
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Fuel Cost Analysis
Based on 15,000 miles/year and current fuel prices.
Efficiency Breakdown
Estimated Lifetime Carbon Footprint
(Based on 200,000 miles driven)