Mercedes-Benz OM 471 engine: displacement, ratings and generations

The Mercedes-Benz OM 471 is a 12.8-litre in-line six-cylinder diesel engine from Daimler Truck, built for heavy trucks and listed by Mercedes-Benz Powertrain for buses as well. It belongs to the heavy-duty 47X model series. Mercedes-Benz Trucks launched its third generation in 2022 and, on 13 September 2026, presented a further generation as part of the Powerliner driveline, to be introduced in its vehicles from April 2027. On this site it is one of the engines of the Mercedes-Benz Actros, Actros L and Arocs and of the Setra ComfortClass and TopClass.

Status as of 26 October 2026. Read that day: Daimler Truck’s press releases of 7 April 2022 on the third-generation OM 471 and of 13 September 2026 on the Powerliner driveline, the Powerliner page of Mercedes-Benz Trucks, the Truck Euro VI engine page of Mercedes-Benz Powertrain, and Mercedes-Benz Powertrain’s Truck Euro VI portfolio (dated 09/2025) and Bus Euro VI portfolio. All six are the maker’s own documents.

Maker, name and layout

The OM 471 is a Daimler Truck engine. Daimler Truck’s April 2022 release says the drivetrain around it is manufactured in the company’s own power systems plants and that the Mercedes-Benz Mannheim plant “takes the lead here: a center of competence for heavy-duty commercial vehicle engines from Daimler Truck”. Mercedes-Benz Powertrain, the Daimler Truck unit that offers engine systems, transmissions and axles as components, lists the engine in its truck and bus portfolios.

The name follows the scheme the truck portfolio sets out: OM marks an oil (diesel) engine, then “47 = 47X model series (HD)” and “1 = L6 cylinder engine (12.8 l)”. The engine page gives the OM 471 as “Arrangement: L6 | Displacement: 12.8 l”.

For the heavy-duty series as a whole, Mercedes-Benz Powertrain lists six-cylinder diesel engines in an in-line arrangement with cooled exhaust gas recirculation, a common rail injection system of up to 2,700 bar, a 1-stage turbocharger with asymmetrical turbine geometry, two overhead camshafts with 4-valve technology, and a “One box” exhaust after-treatment, which the truck brochure describes as “with SCR and DPF” (how SCR and AdBlue work is covered in SCR and AdBlue explained). It gives engine brakes of up to 480 kW brake power for the heavy-duty truck series and up to 375 kW for its heavy-duty bus engines; it gives no separate engine-brake figure for the OM 471. What an engine brake is, and how the law groups it, is set out in retarders and engine braking.

Euro VI ratings in the Mercedes-Benz Powertrain portfolios

Mercedes-Benz Powertrain’s engine page and its truck brochure of 09/2025 list five ratings for the OM 471, each with rated power at 1,600 rpm and maximum torque at 1,100 rpm. The bus brochure lists two of them. Its index marks the other three with the footnote “Output level only available for trucks.”

How kW and hp relate, and what the engine speed beside each figure means, is explained in reading truck power figures.

The two brochures also give the engine’s weight and size, both “depending on equipment installed”. The truck brochure lists 1,078 kg (DIN 70020 - GZ) and a length of 1,551 mm, a width of 1,130 mm and a height of 1,245 mm. The bus brochure lists 1,104 kg and a length of 1,307 mm, a width of 770 mm “excl. charge air pipe” and a height of 1,058 mm.

Generations

Daimler Truck’s documents distinguish three stages of the engine: the first two generations, the third generation of 2022 and the Powerliner generation. The first two are not dated in any of them.

Third generation, 2022

Daimler Truck’s release of 7 April 2022 says the third generation is “now available to order and available from October 2022”, installed in the Mercedes-Benz Actros and Arocs. The geometry of the piston recess, the injection nozzle design and the cylinder-head parameters for gas exchange were reworked; in the release’s words, “the compression ratio of the six-cylinder in-line engine has been increased from 18.3:1 to 20.3:1”, with a peak ignition pressure of 250 bar.

Two turbochargers developed and manufactured in-house came with it. The release assigns the “consumption-optimized variant” to long-distance haulage “with an engine rated at up to 350 kW (476 hp)”, and the second, the high-power variant, which it describes as designed for a high engine braking force, to the heavy-duty and construction sector “with an engine rating of up to 390 kW (530 hp)”. The high-power variant is also used on the lower ratings for the construction applications of the Arocs. The third generation also has an electrically actuated, map-controlled engine oil pressure control valve, and a newly developed exhaust gas aftertreatment system with NOx sensors, an adaptive NOx closed-loop control circuit and a predictive SCR temperature model, which the release says is compliant with Euro VIe.

The release also describes an extended Top Torque range: for the 330 kW (450 hp) and 350 kW (476 hp) output levels in conjunction with the G281 transmission, “200 Nm torque is available to the crankshaft in gears 7 to 12” in the “A Standard” program.

Powerliner generation, from April 2027

On 13 September 2026 Daimler Truck presented the Powerliner, a new driveline generation with “enhanced OM 470 and OM 471 engines as well as coordinated transmissions and axles”. The new driveline generation will be introduced in Mercedes-Benz Trucks vehicles from April 2027, and the release says the new engine generation will also be used in vehicles from Daimler Buses. The Mercedes-Benz Trucks Powerliner page says the new Powerliner generation builds on the Powerliner of the late 1980s.

For the OM 471 the release lists four power ratings: 310 kW/421 hp, 330 kW/449 hp, 365 kW/500 hp and a new top rating of 400 kW/550 hp. “Depending on the power rating, the engine delivers maximum torque of 2,200 Nm, 2,500 Nm, 2,650 Nm or 2,800 Nm.” Full torque is available “at engine speeds well below 1,100 rpm” and reaches its maximum at 1,100 rpm. Among the contributing factors in the engine’s architecture the release names a new injection system, in-house developed and application-specific turbochargers, and changes to the oil circuit, and it describes the engine characteristics as designed around a downspeeding concept.

Fuels and emission class

Mercedes-Benz Powertrain lists the OM 471 among its six-cylinder diesel engines, and none of the documents read for this page lists a gas-fuelled version. For the Powerliner generation, Daimler Truck’s September 2026 release states: “Certification for operation with CO₂-neutral EN 15940 XtL fuel is also available.” The Mercedes-Benz Trucks Powerliner page says the drivetrain is certified for operation with EN 15940 XtL fuel. The documents do not use the term HVO; what the EN 15940 standard covers is set out in what is HVO fuel.

Mercedes-Benz Powertrain lists the OM 471 among its Euro VI engine systems. For the third generation of 2022, the April 2022 release says its newly developed exhaust gas aftertreatment system is “compliant with the strictest emission standards, such as Euro VIe”. The September 2026 release sums up the Powerliner generation as “Designed for Euro VIe, aligned with new statutory noise regulations from start of production, and conceptually prepared for Euro 7.” The Powerliner page writes the same step as Euro 6e and says the drivetrain is designed to comply with it over its entire service life. The steps from Euro VI A to E and what Euro 7 adds are covered in Euro VI and Euro 7.

Trucks and buses on this site with the Mercedes-Benz OM 471

Five model pages on this site list the OM 471 among their engines. The figures below are those recorded on each model’s own page; they are not the engine-level tables above.