BMW B58 Engine for Sale | OEM Used 3.0L Turbocharged Inline-6 (340i, M340i, GR Supra)

Description

About the BMW B58 Engine

The BMW B58 is widely regarded as BMW best modern turbocharged Inline-6 engine and one of the strongest turbocharged engines produced by any manufacturer in its displacement class. Introduced in 2015 as the replacement for the N55, it has been named to the Ward 10 Best Engines list five times (2016, 2017, 2019, 2020, 2024) and has earned enthusiast praise as “the modern 2JZ” for its combination of factory reliability and extraordinary tuning potential on stock internals.

Two Engineering Decisions That Made the B58 Different

Two engineering decisions made the B58 fundamentally different from the N55 it replaced:

First, a closed-deck block design: unlike the N55 open-deck construction where the cylinder walls have gaps in the water jacket, the B58 has solid material surrounding the cylinder walls throughout. This dramatically reduces cylinder bore distortion under boost and heat, improving both reliability and the engine ability to handle high boost pressure.

Second, a forged steel crankshaft and drop-forged cracked connecting rods: components that are meaningfully stronger than the N55 comparable hardware and have been documented to survive 600 to 700 horsepower on stock internals.

The B58TU1 Technical Update

The B58TU1 technical update introduced in 2018 to 2019 added a larger turbocharger, revised cylinder head with improved combustion chambers, a higher-pressure fuel injection system (350 bar vs the Gen 1 200 bar), and split the B58 into ML (335 hp, middle output) and OL (382 hp, high output) variants. The OL variant powers the M340i, M240i, Z4 M40i, and Toyota GR Supra 3.0, the same engine architecture used in multiple brands simultaneously.

Signs You Need a Replacement Engine

• Coolant loss without visible external leak, cracked plastic expansion tank (common on higher-mileage B58 units) or water pump failure
• Oil leaks at valve cover gasket or oil filter housing, the two most common B58 external oil leak points
• Rough idle or misfires, carbon buildup on intake valves from direct injection, particularly on high-mileage examples (carbon buildup requires walnut blasting to clean)
• PCV system fault codes or oil mist in intake, PCV valve built into the valve cover can fail causing crankcase pressure buildup
• VANOS fault codes or rough running, VANOS solenoid wear on high-mileage units or those with extended oil change intervals
• Turbo wastegate rattle at idle, more common on tuned engines running higher boost, audible as a faint rattling at idle

Known Problems With This Engine

Carbon buildup on intake valves, inherent to direct injection B58 engines: Direct injection sprays fuel directly into the cylinders, bypassing the intake valves. This means the intake valves accumulate carbon deposits from the PCV system without fuel washing them clean (as port injection does). At 50,000 to 60,000 miles most B58 engines benefit from walnut blasting to clean the intake valves. Symptoms include rough idle, hesitation, and reduced response. This is a maintenance item, not a defect.

Valve cover gasket leak: The valve cover gasket on the B58 seeps with age, typically becoming apparent at 50,000 to 100,000 miles. This is more common on engines run at high temperatures frequently. We inspect the valve cover area before shipping.

Cooling system: The B58 plastic coolant expansion tank and water pump housing can crack under repeated heat cycling. We inspect the cooling system connection points before shipping. Service the cooling system completely at installation.

PCV valve failure: The PCV (positive crankcase ventilation) valve is integrated into the B58 valve cover. PCV failure causes increased crankcase pressure and oil consumption. We note any PCV-related indicators before shipping.

B58 Gen 1 vs B58TU1 compatibility: The Gen 1 B58 (2015 to 2017) and the B58TU1 (2018 onward) have different cylinder heads, ECU calibrations, and some different ancillary components. They are not directly interchangeable without ensuring matching ECU and wiring. We confirm the generation before every order ships.

BMW B58 Generations and Power Variants

What Ships and What Does Not

Vehicle Compatibility

The BMW B58 family powers an extensive range of BMW and Toyota vehicles:

The B58 is popular in the tuning and swap community due to its closed-deck construction and extraordinary tuning potential. Common swaps include into older BMW E-series chassis and custom builds. Proper ECU integration is the most complex aspect of any B58 swap.

Transmission compatibility: ZF 8HP 8-speed automatic (standard on most B58 applications), BMW 6-speed manual (available on select models including 340i, M240i). Confirm your specific vehicle transmission before ordering.

Inspection Workflow

Every used BMW B58 we ship goes through this process:

• Full external inspection, block, head, valve cover area, cooling system connection points, and all accessible engine surfaces
• B58 generation confirmed, B58B30M0 or B58TU1 ML/OL documented before shipping
• Valve cover gasket area inspected for seepage
• Cooling system expansion tank and water pump housing inspected for visible cracking
• PCV valve cover integration inspected for indicators
• VANOS solenoid area inspected
• Carbon buildup assessment where accessible, intake manifold area inspected

Mileage varies by unit. Where available from the donor vehicle we provide it. Where it cannot be confirmed, we disclose this before your order is placed.

Buyer Tips, What to Know Before You Order

• Service the cooling system at installation: Replace the expansion tank and water pump at installation regardless of apparent condition. Both are known failure points on B58 engines over 60,000 miles. The cost is approximately $300 to $500 in parts. The cost of an overheated B58 is catastrophic.
• Carbon buildup, plan for walnut blasting: Direct injection engines like the B58 accumulate carbon on intake valves over time. At installation or within the first 10,000 to 15,000 miles, arrange for a walnut blasting service to clean the intake valves.
• B58 Gen 1 vs B58TU1 ECU compatibility: The Gen 1 and TU1 use different ECU calibrations. Confirm that the replacement engine generation matches your vehicle existing ECU and wiring harness configuration.
• Oil quality and intervals: Use BMW-approved full synthetic 0W-30 or 5W-30 meeting BMW Longlife-17 FE+ specification. Change every 7,500 miles maximum for performance longevity.
• Tuning potential: If you plan to tune the B58, the closed-deck block can handle significantly more boost than the N55. Stage 1 tunes typically produce 370 to 420 hp on stock internals. Built motor packages at 500 to 700 hp have been well documented.

Why Buy From Part Nests

• B58 generation confirmed, B58B30M0 or B58TU1 ML/OL documented before you pay
• Valve cover, PCV, and cooling system connection points specifically inspected
• Full external inspection documentation before shipping
• Carbon buildup assessment disclosed, buyers prepared for walnut blasting service
• No core charge, keep your old engine
• Free freight pallet delivery to all 50 states
• 15 day replacement warranty on internal engine defects
• Call (240) 306-7051, speak with someone who understands B58 generations and the key differences from the N55
• Call (240) 306-7051 to confirm B58 generation (Gen 1 vs TU1 ML vs TU1 OL), donor application, and ECU compatibility before ordering