The Most Reliable Six-Cylinder Engines

The six-cylinder engines convince with their work culture, sound and parameters. There is no shortage of cars with such engines on the secondary market. We present the best engines of this type.

The power source has a very large impact on the driver’s perception of the car. A powerful, smooth-running and durable engine increases the comfort of operation. So it should come as no surprise that despite high fuel prices, many people are looking for in-line six-cylinder engines. Although such engines were offered by only a few brands, there is a lot to choose from. What is equally important – both those interested in petrol and diesel engines will find something for themselves.

This The Best Choice Of The Six-Cylinder Engines

Below we present the best in-line “sixes”. We focused on engines available in not too old models that can still be used for everyday use. Whoever is looking for a youngtimer or a classic will have an even greater choice, because in-line six-cylinder engines are not a novelty on the market – they have been used for years in models designed to provide high comfort or above-average performance.

BMW 2.0/2.5/2.8 M52 petrol engine

  • Displacement: 1990/2494/2793 cm³, Maximum power: 150-193 hp, Production years: 1994-2000

One of the engines that built the BMW legend was the excellent M50. Its place was taken by the equally solid and noticeably more flexible M52. The engine debuted in 1994 and was offered until 2000. Making the block of aluminum instead of cast iron significantly reduced the weight of the engine, while the VANOS on the intake shaft improved the characteristics of the engine.

The M52 engine was available in versions with a capacity of 2.0, 2.5 and 2.8. We recommend the last two with an indication of 2.8, which provided excellent performance, with fuel consumption slightly higher than that observed in weaker versions.

M52 engines can be found in the BMW 3, 5 and 7 series and the Z3 roadster. They are in demand especially in combination with a manual gearbox. The market is so disguised and the prices are so high that it may be a good idea to buy a car with an automatic transmission and then change the gearbox. Good performance meant that many cars were literally tortured.

In turn, opinions on the durability of the M52 engine encouraged many drivers with less affluent wallets to save on servicing. Especially in combination with LPG installations, this meant problems with the cooling system, often resulting in overheating of the cylinder head.

In 1998, the M52 engine was modernized – it received a DISA valve in the intake manifold and a phase variator on the exhaust camshaft, which increased service costs. If the ignition after a long stop is accompanied by bluish smoke from the exhaust pipe, valve seals need to be replaced.

In the M52 engine, they are most often to blame for excessive oil consumption.You also need to remember about the need to replace the pneumothorax filter. Omission of this step leads to obstruction of the pneumothorax.

As in other BMW engines, care for the cooling system, regular oil changes and the use of a branded lubricant filter are also necessary. The invested M52 engine will repay you with longevity, good performance and unique sound.

Presence of the BMW 2.0/2.5/2.8 M52 engine:

  • BMW: 3 series E36/E46, 5 series E39, 7 series E38, Z3

BMW 2.2/2.5/3.0 M54 petrol engine

Displacement: 2171/2494/2979 cm³, Maximum power: 170-231 hp, Production years: 2000-2006

While it may have seemed impossible to improve the M52 engine, BMW engineers have succeeded. The M54 engine is considered one of the best construction in the history of the brand. It was available from 2000 to 2006 in 2.2, 2.5 and 3.0 capacity variations.

They developed 170-231 hp, very evenly distributing power and torque. All this with the demand for fuel, which, when driving calmly, was easily within 10 l / 100 km. The engine has indirect fuel injection and dual Vanos, but has not received the potentially troublesome Valvetronic system.

The M54 engine went to the BMW 3, 5 and 7 series, the X3 and X5 models and the Z3 and Z4 roadsters. Even used engines cost a lot, because they are willingly swapped (transferred) to older BMW models. Excellent opinions about the M54 engine result from its high work culture, high power obtained without the help of turbo and above-average durability.

Recurring faults can include thermostat failures.The biggest concern for BMW users with M54 engines is oil consumption. Valve seals and the design of the pneumothorax may be to blame, but just as often oil burning stops after replacing the piston rings. As in the older M52, it is also worth checking the oil separator in the pneumothorax.

Presence of the BMW 2.2/2.5/3.0 M54 engine:

  • BMW 3 Series E46, 5 Series E39/E60, 7 Series E65, Z3, Z4 E85, X3 E83, X5 E53

BMW 3.0 B58 petrol engine

Displacement: 2998 cm³, Maximum power: 286-388 hp, Years of production: from 2015

After the excellent M54 engines, BMW engineers began to modernize the six-cylinder engines, mounting them, among others. Valvetronic systems, direct fuel injection or turbocharging. Thus, among others, six-cylinder engines N52, N53 and N55. They are not bad, but also not as outstandingly durable as older engines.

Malicious even say that … “N if you don’t buy.” After years of technical experimentation, BMW presented a new family of modular engines – the 1.5 B38/2.0 B48 and 3.0 B58 engines differ in the number of cylinders, which obviously affects the capacity. The top engine B58 enjoys very good opinions.

Some even suggest that it is the best engines in the history of BMW or the best contemporary engine of the brand.

Why? Never before have BMW engines reconciled work culture, durability and susceptibility to tuning with relatively low fuel consumption in such a way. The presence of turbocharging is practically imperceptible – the engine gives off power and torque without delay.

Anyway, the exorbitant prices of used cars with the B58 engine are probably the best recommendation. The most frequently reported faults of BMW B58 engines concern coolant loss, valve cover gasket leaks, problems with pneumothorax and incorrect operation of the VANOS system solenoids.

Presence of the BMW 3.0 B58 engine:

  • BMW 1 Series F20, 2 Series F22/G42, 3 Series F30/G22, 4 Series F32, 5 Series G30, 6 Series G32, 7 Series G11/G70, 8 Series G14, X5 G05, X6 G06, X7 G07, Z4 G29
  • Ineos Grenadier
  • Toyota Supra A90

Diesel BMW 2.5/2.9/3.0 M57

Displacement: 2497/2926/2993 cm³, Maximum power: 163-286 hp, Production years: 1998–2008

The six-cylinder diesel engine of the BMW M57 can only be described in superlatives. It has bearish strength, can be economical, sounds pleasant, has a high work culture, and is also extremely durable and relatively cheap to repair.

Interestingly, the older and weaker the M57 version, the easier and cheaper it is to service and more reliable. This is mainly about the hardware, because the strength reserves inherent in the block of this engine are huge. It was no coincidence that the X-raid team used the M57 engine to create the heart of the BMW X3 Cross Country Dakar rally car, which developed 315 hp and 700 Nm. The road version of the M57 engine was available in 2.5, 2.9 and 3.0 displacements.

BMW assembled this diesel engine for the 3, 5, 6 and 7 series, X3, X5 and X6 models, as well as made this engine available for the Range Rover L322 (2.9) and Opel Omega B (2.5), where it appeared under the designation 2.5 DTI in 2001 -2003. Were it not for general fatigue and real mileage of over 0.5 million kilometers, the 2.9-liter version with 184 hp would be the best choice.

It has the least complicated equipment and electromagnetic injectors that are easy to regenerate. Newer versions of the engine include flaps in the intake manifold, and more powerful versions received double turbocharging or piezoelectric injectors. In a car with high mileage, this will mean increased maintenance expenses.

To keep your M57 engine in the best possible condition for many years, you should remember about regular oil changes, periodically check the efficiency of injectors and use branded replacements or genuine parts. In this case, the bill for the service will not be record low, but you will be able to enjoy the peace of operation – e.g. the timing belt should withstand another 400,000 km. and more powerful versions received twin turbocharging or piezo injectors.

In a car with high mileage, this will mean increased maintenance expenses. To keep your M57 engine in the best possible condition for many years, you should remember about regular oil changes, periodically check the efficiency of injectors and use branded replacements or genuine parts.

The M57 diesel is succeeded by the 3.0-litre N57, available from 2008 to 2019. It is also a successful engine, which does not have as many problems with the timing drive as the two-liter N47 (over time in the 3.0 engine the slide falls apart, but the chain is not pulled out).

A significant degree of complexity, resulting from, among others, the expansion of equipment responsible for exhaust gas purification, combined with extended service intervals and neglect of some cars, may translate into the cost of repairs of some N57 engines.

Presence of the BMW 2.5/2.9/3.0 M57 engine:

  • BMW BMW 3 Series E46/E90, 5 Series E39/E60, 6 Series E63, 7 Series E38/E65, X3 E83, X5 E53/E70, X6 E71
  • Opel Omega B
  • Range Rover L322

Mercedes 2.8/3.0/3.2/3.4/3.6 OM104 petrol engine

Displacement: 2799/2960/3199/3314/3598 cm³, Maximum power: 193-280 hp, Production years: 1989-1997

Before Mercedes started to offer V6 engines, it offered its customers models with in-line sixes, which had varieties that differed in power and capacity, but equally few failures. Typical faults include problems with the wiring harness, flow meter or coils. It is also worth being prepared for high fuel consumption.

Drivers claim, however, that this can be compensated by the LPG installation, with which the engine is supposed to work well. For some drivers, the downside may also be the rather mild characteristics of most versions of the OM104 engine – apart from the top ones, available in models signed by AMG. Who is looking for a six-cylinder spark fire should rather be interested in the BMW.

Presence of the Mercedes 2.8/3.0/3.2/3.4/3.6 OM104 engine:

  • Mercedes C-Class W202, E-Class W124/W210, S-Class W140, SL R104

Diesel Mercedes 3.2 OM613/OM648

Displacement: 3222 cm³, Maximum power – OM613: 197 hp; OM648: 177-204 HP, Production Years – OM613: 1999-2003; OM648: 2002-2006

Mercedes engineers created a range of technically similar OM611, OM612 and OM613 diesels, which were created as a result of adding more cylinders and modifying the equipment. With proper service care, cars with such a power source easily covered over 0.5 million km without major failures.

The problem is that a large percentage of cars with this engine are past their prime and require additional investment. One of the weaker points of the engines is the cooling system, including thermostats. It is worth checking its condition, because overheating of the engine can lead to cracking of the cylinder head.The repair costs will then be counted in thousands of dollars, which is based on the current market values ​​of the vehicles to which it was delivered.

The good news is the relatively simple construction of many components and their interchangeability with parts provided for 4- and 6-cylinder diesels. This means, respectively, the possibility of regeneration and good access to replacements. The evolution of the OM613 engine is the modernized OM648, which differs from the original in hardware and pistons.

Occurrence of diesel OM613/OM648:

  • Mercedes: E-class W210/W211 and S-class W220

Toyota/Lexus 2.5/3.0JZ petrol engine

Displacement: 2492/2997 cm³, Maximum power: 170-324 hp, Production years: 1990-2007

The title of the best six-cylinder engine from Japan is enjoyed by the iconic engines from the JZ family (1990-2007) – 1JZ (2.5) and 2JZ (3.0). They were made famous by their work culture, sound, durability and susceptibility to tuning – over 400 HP could be extracted from the supercharged variants without replacing the pistons or connecting rods with more solid ones. The problem is that currently buying a car with such a power source is difficult and expensive.

We would like to remind you that we are talking about a legendary source of power that set in motion, among others Toyota Supra.Who would like to experience driving a car with a JZ engine in a relatively reasonable budget, has only a few Lexus models to choose from, which are not very common. If you find a copy in good condition, it is worth taking an interest in it, because with proper service care, the car will last forever. Potential problems are limited to burning larger amounts of oil or faulty equipment – mainly sensors.

2JZ engine presence:

  • Lexus: IS 300/GS 300/SC 300 (the most common models on the European market, and also the cheapest)

It is worth noting that the 155-horsepower 2.0 1G-FE engine fitted to the first Lexus IS also performs well in terms of durability, refinement and sound. For some drivers, its drawback will be quite high-revving characteristics – the maximum 195 Nm is available only at 4600 rpm.

Volvo Modular 2.5/2.8/2.9 engine

Displacement: 2473/2783/2922 cm³, Maximum power: 170-272 hp, Production years: 1991-2006

Engines from the Volvo Modular family are one of the greatest legends of modern engine. At the end of the 20th century, the Swedish concern created a family of engines whose capacity was regulated by changing the diameter and stroke of the piston and the number of cylinders, which could be 4, 5 or 6. The most recognizable are the armored and great-sounding five-cylinders.

Less common, due to availability in larger models, are engines with six cylinders, the factory code of which begins with the characters B6. Most of them are naturally aspirated, although marked with the T6 symbol, and fitted to the S80 and XC90, the 2.8/2.9 engines are equipped with twin turbocharging.

The overall durability of Volvo Modular engines is high.Potential problems are most often due to wear and tear and the age of the car. Most often, equipment fails – including throttles and flow meters. Oil spills are not uncommon. In more powerful versions, automatic gearboxes “give up” relatively early. Also, do not forget about the need to periodically replace the timing belt.

Presence of the Volvo Modular 2.5/2.8/2.9 engine:

  • naturally aspirated 2.9 – Volvo 960, S80 I, S90 I, V90 I XC90 I
  • turbocharged 2.8/2.9 T6 – Volvo S80, XC90

3.0/3.2 Volvo SI6 petrol engine (Short Inline 6)

Displacement: 2953/3192 cm³, Maximum power: 233-350 hp, Production years: 2006-2015

The final version of the six-cylinder Volvo engine draws on the achievements of the older Modular engines – contrary to appearances, it is not a Ford engine, as many people think, but an original design of the Swedish brand. Talking about the company under the sign of the blue oval in the context of the SI6 engine, however, does not make sense – it was created when Volvo belonged to Ford, and the Ford factory in the UK was responsible for productionBridgend.

Why was this step taken? It is possible that the Ford concern was thinking about using this engine more widely in its cars. Finally, apart from Volvo, we will find it only in the Land Rover Freelander 2. The SI6 engine has a 3.2 and 3.0 capacity version. The first is naturally aspirated and equipped with intake length adjustment systems, variable valve timing on the intake shaft and variable valve lift, the second – supercharged and with adjusters for both camshafts.

The list of potential faults is short. Includes problems with the READ roller, i.e. the accessory drive system, water pump failures (mainly in early production engines), pneumothorax damage, oil leaks and lubricant burning– the latter mainly in engines manufactured before 2012, later it was limited by changing the design of the piston rings.

The transverse installation of the engine and torques of up to 500 Nm put automatic gearboxes to the test. The key to its life is not only the reasonable treatment of the car, but also changing the oil in the transmission.

Some drivers try to compensate for high fuel consumption by installing an LPG system, which, in their opinion, works well in these engines. The potential buyer of the car must also accept the high costs of servicing, which result from, among others, from the tight housing of the engine under the hood.

Presence of the Volvo SI6 engine:

  • 3.0 (marked as T6, and in the top version in the S60/V60 as the Polestar version – Volvo S60 II, V60 I, V70 III, XC70 II, S80 II, XC60 I
  • 3.2 – Volvo V70 III, XC70 II, S80 II, XC60, XC90
  • Land Rover Freelander 2

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