The truck diesel engine is even more dependant on economic efficiency than the motor car diesel engine. There is more to it than only the fuel economy, which can be, over long distances sometimes less than 30 l/100 km, on difficult tours and with construction site vehicles, it can also be up to about 50 l/100 km. The mileage performance is also important (approx. 1 million km, the record is 2 million km).
As a rule, heavy utility vehicles have engines with a cubic capacity of up to 16 liters, mostly straight 6-, V6 or V 8 engines (more seldom 10 cylinders.) with a max. torque of more than 2000 Nm already at approx. 1100 RPMs and an engine weight of max. 1000 kg. The maximum RPMs are 2200-2500, compared to 4500 to- over 5000 RPMs in the motor car. American 6 cylinder diesel engines can have even more individual cyl. displacement with cubic capacities of up to 2.7 l. They have a compression ratio 16:1, slightly lower than European manufacturers (18:1), they have however, a higher boost pressure. Thus they reach higher performances (over 600 HP). Modern European truck engines are low-emission (Euro 3 standard with a slightly higher consumption) and thus achieve the same pollution standard as motor car diesels, indeed, under different testing conditions.
In the event of unfavorable exhaust gas values, the air filter should be examined first, and only afterwards the fuel injection system or the engine (e.g., the compression). 10/09