BMW M4 S55 3.0L Twin-Turbo Inline-6 Engine

BMW M4 S55 Engine for Sale. Low Mileage 3.0L Twin Turbo Inline 6 Replacement.

The BMW M4 S55 engine is one of the most capable inline 6 engines BMW has produced in the modern M series lineup. If you own a BMW M3, M4, or M2 Competition and need a replacement engine after an internal failure, a rod bearing issue, or a mechanical problem that makes replacement more practical than repair, a clean low mileage S55 3.0L twin turbo engine from a verified donor vehicle is the direct path back to factory spec. At McClain Auto Part, we have been sourcing and selling used performance engines out of Cleveland, Ohio since 2009. The BMW S55 engine is one of the most specialized high performance units we carry.

BMW M owners come to us for a few reasons. Some deal with the documented rod bearing failure that affects higher mileage S55 engines, particularly on cars that have seen track use or extended high RPM operation without bearing service. Others are rebuilding an M3 or M4 that has been in an accident and needs a fresh engine with verified mileage. A smaller group is doing a swap project into a classic BMW chassis or a custom build where the S55 twin turbo output is the target.

Whatever the situation, the goal is the same. A tested, documented BMW M4 engine that installs correctly and performs the way the car is supposed to.

Key Features

• BMW M4 S55 engine, OEM BMW M division unit
• 3.0L twin turbo inline 6, genuine S55 assembly
• Low mileage, verified from donor vehicle records
• Compression tested on all six cylinders before shipping, numbers recorded
• Full visual inspection completed at our Cleveland facility
• Rod bearing condition noted on every unit
• Twin turbocharger system inspected before shipping
• Oil condition and coolant passages checked before packaging
• 6-month warranty against internal mechanical defects
• Ships freight to all 50 states from Cleveland, Ohio
• Most orders processed within 1 to 3 business days

The BMW S55 Engine Platform

The S55 is the high performance version of BMW’s B58 and N55 modular inline 6 architecture. BMW developed the S55 specifically for M division applications. It shares the basic inline 6 configuration with other BMW 3.0L engines but uses a different cylinder head, revised block casting, upgraded internals, and a twin turbocharger system rather than the single turbo found on the N55. The result is a purpose-built M division engine rather than a detuned version of a standard production unit.

Twin Turbo System

The 3.0 twin turbo BMW inline 6 engine uses two small twin scroll turbochargers rather than a single larger unit. Twin scroll technology improves turbocharger response by separating exhaust pulses from pairs of cylinders into dedicated scroll channels within the turbine housing. As a result, spool time is reduced and throttle response at partial load feels closer to a naturally aspirated engine than a traditional single large turbo setup. In factory M4 trim, the S55 produces 425 horsepower and 406 lb-ft of torque from 3.0L of displacement.

S55 Versus N55

If you are sourcing a replacement for an M3 or M4, the S55 is the correct unit. The N55 is the standard production 3.0L single turbo found in the 335i, 435i, and similar non-M applications. The two engines share basic architecture but differ in head casting, turbocharger system, oil system, connecting rods, crankshaft, and output. They are not interchangeable. If your M3 or M4 needs an engine, source an S55, not an N55.

Rod Bearing Consideration

The S55 rod bearing issue is well-documented in the BMW M community. The factory rod bearing specification is a known wear item on higher mileage S55 engines, particularly on cars that have seen track use, aggressive driving, or oil service intervals longer than recommended. We inspect every S55 unit for rod bearing condition before it ships and document those findings in our pre-ship report. Buyers who want additional peace of mind should plan to replace rod bearings on installation regardless of the unit’s mileage. We can advise on this when you call.

Technical Specifications

Specs vary slightly by model year and market. Call us with your VIN before ordering to confirm the correct variant for your vehicle.

What Is Included

Included components vary by unit. Here is what a typical used BMW S55 motor package from McClain includes.

Standard With Most Units

• Complete S55 long block assembly
• Intake manifold and charge pipe connections
• Direct injection fuel rails and injectors
• Valve covers
• Oil pan
• Twin turbocharger assembly, condition documented
• Double VANOS units, intake and exhaust
• Oil filter housing

Available on Select Units or by Request

• Engine wiring harness
• ECU, DME
• Intercooler and charge pipe system
• Front accessory drive components
• Coil packs and ignition components
• Oil cooler assembly

A Note on DME and Wiring

The S55 DME is coded to the vehicle VIN. For a direct factory replacement in the original car, your existing DME is typically reused and coding is performed to the new engine. For a swap application or a replacement in a different chassis, DME coding and VIN matching is required. This is a step that needs to be planned before installation. Tell us your application when you call and we advise on what the DME and wiring situation requires for your specific build.

Condition and Inspection

Every BMW S55 engine replacement unit that ships from our Cleveland warehouse goes through a detailed inspection. The twin turbo system, rod bearing condition, and direct injection fuel system on the S55 require specific attention that simpler naturally aspirated engines do not.

What We Check Before Every Unit Ships

• Compression test on all six cylinders, actual numbers recorded
• Full visual inspection of block, head, and external surfaces for cracks, leaks, or damage
• Oil condition checked for contamination, metal particles, or signs of bearing distress
• Coolant passages inspected for signs of mixing or head gasket issues
• Mileage verified against donor vehicle documentation
• Rod bearing condition noted, oil clearance indicators documented where accessible
• Twin turbocharger assembly inspected for shaft play, housing condition, and oil feed line integrity
• Direct injection fuel rails and injectors inspected for seal condition and rail integrity
• Double VANOS units checked for condition and solenoid connector integrity
• No audible knocking, ticking, or unusual engine noise confirmed before packaging

Rod bearing condition and turbocharger condition are documented separately on every unit before it ships. You receive that documentation before the order is finalized.

Vehicle Compatibility

The BMW S55 engine was factory-fitted in the following vehicles:

• BMW M3 F80 sedan, 2015 to 2018
• BMW M4 F82 coupe and F83 convertible, 2015 to 2020
• BMW M2 Competition F87, 2019 to 2021

Before ordering, confirm your VIN and build date. The S55 went through minor updates across model years. Fitment depends on your specific vehicle configuration. For M2 Competition applications, confirm the S55 variant as the standard M2 used the N55, not the S55.

Call us with your VIN and we confirm the right unit for your application.

Common Swap Applications

The 3.0 twin turbo BMW inline 6 engine is a growing platform for swap projects outside the factory M chassis. Common applications include:

• E30, E36, and E46 BMW chassis builds
• E9x M3 replacement builds using the S55 over the S65 V8
• Custom tube chassis and track car builds
• Kit car applications requiring a high output compact inline 6

For swap applications, confirm engine mount dimensions, oil pan clearance, cooling system routing, and DME solution before ordering. The S55 fuel and ignition systems require a functioning DME solution to operate correctly.

Replacement and Swap Notes

Direct Factory Replacement

For a direct BMW M4 engine replacement or BMW M3 engine replacement in the original F80 or F82 chassis, a matching S55 from the same application is the correct approach. DME coding to the replacement engine is required. Most independent BMW specialists and dealer service departments perform this coding. Confirm your shop can perform S55 DME coding before ordering the engine.

Rod Bearing Service on Installation

Given the documented rod bearing wear pattern on the S55, most experienced BMW M specialists recommend replacing rod bearings at the time of engine installation regardless of the replacement unit’s mileage. ACL and Mahle rod bearings in the correct S55 specification are the most common aftermarket choices. This is a relatively straightforward procedure on the bench before installation and eliminates the primary failure risk going forward.

Fuel System

The S55 runs a high pressure direct injection system. The factory high pressure fuel pump is driven off the intake camshaft. Confirm fuel pump condition on the replacement unit before installation. The high pressure pump is a wear item on higher mileage S55 engines and replacement at installation is worth considering alongside the rod bearing service.

Cooling System

The S55 uses a separate cooling circuit for the charge air cooling system in addition to the main engine cooling circuit. Confirm both circuits are properly flushed, filled, and bled before startup. Air pockets in the charge air cooling circuit affect intercooler efficiency and can cause heat soak under hard driving.

Transmission

The S55 was paired with the DCT dual clutch transmission or the 6-speed manual in factory applications. Both use a standard BMW M bellhousing pattern. Confirm your transmission and confirm it is compatible with the replacement engine before ordering.

Shipping and Warranty

Shipping

We ship from Cleveland, Ohio to all 50 states. Every engine ships on a secured freight pallet, fully protected for transit. Most orders are processed and ready to ship within 1 to 3 business days after confirmation and payment. You receive a tracking number once the engine leaves our facility.

Warranty

Every engine we sell comes with a 6-month warranty against internal mechanical defects. Rod bearing condition and turbocharger condition are disclosed and documented before the order is processed. If a covered mechanical failure occurs within the warranty period, contact us. We work toward a fair resolution, whether a replacement engine, credit, or repair guidance depending on the situation.

We have been honoring warranty claims since 2009.

About McClain Auto Part

We have been sourcing and selling used performance and replacement engines out of Cleveland, Ohio since 2009. Over 10,000 engines shipped. Rated 4.9 out of 5 stars across 800 or more verified Google reviews. Every engine we sell is physically in our Cleveland warehouse, inspected by our team, and ready to ship.

We are not a listing aggregator or broker. When you call us about a BMW M4 engine for sale, you are talking to someone who understands the S55 platform, knows the rod bearing and turbocharger considerations specific to this engine, and can give you accurate information about the exact unit in current inventory.

Frequently Asked Questions

What Vehicles Use the BMW S55 Engine?

The S55 was used in the BMW M3 F80 from 2015 to 2018, BMW M4 F82 and F83 from 2015 to 2020, and BMW M2 Competition F87 from 2019 to 2021. Confirm your VIN before ordering.

What Is the Difference Between the S55 and N55?

The S55 is the M division engine with twin scroll twin turbos, upgraded internals, and 425 HP. The N55 is the standard production 3.0L single turbo found in non-M applications. They are not interchangeable.

Is This a Direct Replacement for My M3 or M4?

Yes, for F80 M3 and F82 M4 applications equipped with the S55. DME coding to the replacement engine is required. Confirm your shop can perform this before ordering.

How Many Miles Are on the Engine?

Mileage is verified from donor vehicle records. We give you the exact mileage on the specific unit before you commit to the order.

Is the Engine Compression Tested?

Yes. Every cylinder is compression tested before the unit ships. We record the actual numbers and provide them on request.

What About the Rod Bearing Issue?

Rod bearing condition is inspected and documented on every unit before shipping. We recommend replacing rod bearings at installation regardless of mileage. We can advise on specification and procedure when you call.

Does It Include the Turbos?

Yes. The twin turbocharger assembly is included with most units. Turbo condition is documented before shipping.

Does It Include a Wiring Harness and DME?

Not automatically. Harness and DME are available on select units. Tell us your application when you call and we confirm what is in stock.

What Does the Warranty Cover?

Six months from purchase against internal mechanical defects. Rod bearing condition and turbocharger condition are documented and disclosed before the sale. Contact us if a covered issue arises.

Ready to Order

If you are looking for a BMW M4 S55 engine for sale, a verified BMW S55 engine replacement, or a clean used BMW S55 motor for an M3, M4, M2 Competition, or swap project, call us. Confirm your VIN and application and we will tell you exactly what we have in stock. Mileage, rod bearing condition, turbocharger condition, included components, and shipping timeline.

Clean S55 inventory is limited by the production volume of the M3 and M4. If you have questions before committing, ask them.

McClain Auto Part. Cleveland, Ohio. In business since 2009.