BMW G20 M340i / M440i B58 Gen 2 RWD Long Block Engine

Upgrade or restore your BMW G20-series performance with this OEM 2021 BMW M340i / M440i B58 Gen 2 RWD Long Block Engine. Pulled from a 2021 M340i (VIN: 3MW5U7J02M8B53070) with only 30,066 miles, this B58D engine is a high-performance 3.0L inline-6 turbocharged powerhouse engineered for precision, torque, and turbocharged efficiency.

Please note: This long block is sold AS-IS due to a cylinder 5 compression issue. A boroscope revealed a foreign metal object impact on the cylinder head during testing. Cylinder 5 may require rebuild. Despite this, the engine is confirmed to turn, with no cracks in the block or head. Ideal for rebuild projects or core replacement.

Includes a 90-day warranty on the long block (cylinder head + block only). Must ship to a commercial address—please inquire prior to purchasing.

Perfect for enthusiasts, performance shops, and rebuild specialists looking for an authentic BMW B58 Gen 2 platform to restore or upgrade their M340i/M440i.

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 Product Specifications:

• Engine Type: OEM BMW B58D Gen 2 Long Block

• Configuration: RWD (Rear-Wheel Drive)

• Vehicle Compatibility: 2020–2023 BMW G20 M340i / G22 M440i

• Mileage: 30,066 miles

• Donor VIN: 3MW5U7J02M8B53070

• Original Car: 2021 BMW M340i

• Engine Code: B58D

• Transmission: Automatic (not included)

• Compression Test Readings: 189 | 191 | 196 | 199 | 112 | 192

• Exterior Color of Donor: Mineralgrau Metallic (B39)

• Interior Color: Black Sensatec (KCSW)

• SKU: 33599

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 Important Notes:

• Cylinder 5 may require rebuild—visible signs of head damage and wear from prior foreign object.

• Buyer assumes responsibility for reusing accessories left on engine; sold for convenience only.

• Warranty valid only when installed by ASE-certified shop or BMW dealership.

• Overheating, oil starvation, or improper installation voids warranty.

• Residential shipping incurs additional charges—commercial address required for delivery.

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Why Choose a B58 Gen 2 Long Block?

The BMW B58D Gen 2 is among the most robust and tunable inline-6 platforms on the market, designed for both daily luxury and track-day performance. Paired with the G20 chassis, it offers a refined driving experience with torque-focused tuning potential. Whether you’re building a custom M340i/M440i swap, replacing a blown engine, or sourcing a core for rebuild, this long block is a high-value investment with OEM reliability.