The M54 engines are known for their power and reliability. With proper and timely maintenance, the power units can cover over 300,000 kilometers. Some drivers, however, mention in their reviews that they were able to reach up to 350,000 kilometers without major repairs.
Lineup
The range of power units of this type does not vary much in terms of variety. Manufacturers have released 3 samples of engines:
- M54B30;
- M54B25;
- M54B22
Each model has unique properties and technical characteristics. The difference between the engines is slight but noticeable.
M54 Series M54B30 Engines
The elder M54 engine. The Bavarians produced the model from 2000 to 2006. Compared to the «ancestor» M52TUB28, the unit received an aluminum cylinder block with cast iron liners. However, other elements were modified. The M54B30 features a steel crankshaft, lighter pistons, and new connecting rods. A new intake manifold was installed on the cylinder head.
Changes also affected the camshaft, injectors, and throttle. The latter was equipped with electronic control.
The technical characteristics of the elder engine in the series are impressive. The model delivers 231 horsepower with a torque of 300 N*m. Fuel consumption is quite high. In mixed driving conditions (city+highway), the engine consumes 9.8 liters of gasoline. On the highway, the consumption is slightly lower, but in urban settings, covering 100 km will require burning over 10 liters of gasoline.
A drawback of the engine is its fuel requirements. Manufacturers recommend using only AI-95 gasoline. The engine's lifespan may decrease if other gasoline grades are used.
The model was installed in BMW 3, 5, and 7 series cars and used in X3 and X5 crossovers.
The decline of the flagship began in 2004 when the Bavarian automaker introduced the N52 series. The presence of M54B30 in BMW vehicles became rarer and rarer. The company completely discontinued the production of this power unit in 2006.
The engine is good, but not without its issues. In reviews, drivers mention 2 main drawbacks:
- High oil consumption.
- Overheating.
Oil consumption is due to design flaws in the piston rings. These components are prone to carbon buildup. The issue can only be resolved by replacing the assembly. Piston rings from M52TUB28 are suitable for this purpose.
Dealing with overheating can only be achieved through preventive measures. Drivers need to constantly monitor the radiator and the entire engine cooling system.
Some car owners also point out another downside. They highlight the engine's demand for oil. One must forget about saving on purchasing cheap oil blends.
M54B25
This engine from the M54 series was introduced in 2000. Manufacturers primarily modified the connecting rods and pistons. The intake manifold became slightly shorter, allowing for a significant increase in power for the 2.5-liter power unit. The cylinder block remained unchanged.
The unit delivers 192 horsepower. Meanwhile, the torque is 237 N*m. Manufacturers recommend using the same AI-95 gasoline. In terms of fuel requirements, this engine is no different from its older counterpart in the lineup.
The M54B25 model was installed in 4 cars:
- BMW 525i E60 and E39;
- BMW 325i E46;
- BMW X3 E83.
The phase-out period for this model started actively in 2005 and concluded within 12 months. The new vehicles no longer use this power unit.
In reviews about this engine in the M54 lineup, drivers point out typical issues of the series. However, in addition to oil consumption and overheating, another drawback is ignition misfire. The problem arises due to rapid carbon buildup. Replacing the hydraulic lifters can address this issue.
Drivers also note another downside. With high mileage, the engine may rattle, lose power, and experience instability in rpm due to wear of the «vanos.»
M54 Series M54B22 Engines
The younger representative of the M54 engine series. The model's construction is similar to those listed above. The power unit differs primarily in technical characteristics. The model delivers 170 horsepower with a torque of 210 N*m. The unit has become more fuel-efficient. While M54B25 and M54B30 consumed 9.8 liters of AI-95 per 100 km in mixed driving conditions, M54B22 consumes 0.8 liters less.
The 2.2-liter engine was installed in only 3 series of cars:
- BMW 520i E60 and E39;
- BMW 320i E46.
The Bavarians produced the unit from 2001 to 2006. The model was later replaced.
In addition to the drawbacks of the «older» siblings, another issue arose. The thermostat and camshaft sensors often fail. With proper maintenance and fuel quality, the model can «last» at least 300,000 km.
Read more: Comparison of Mercedes-Benz GLE Coupe and BMW X6
Operation
In reviews, drivers note that the first «symptoms» of future issues with the M54 engines start to appear after 50,000 km of mileage. The rpm drops, and power decreases. If the driver previously operated the vehicle normally, there is no need to worry about future breakdowns.
