There are two main types of diesel engines used in trucks: inline engines and V-type engines. Inline engines have all of the cylinders arranged in a single row, while V-type engines have the cylinders arranged in two banks that are angled apart from each other. V-type engines are more common in trucks because they are more compact and they produce more power than inline engines.
The size of a truck's engine is measured in liters. The larger the engine, the more power it will produce. However, larger engines also use more fuel. The average truck engine size is between 6 and 10 liters.
Some trucks also use gasoline engines. Gasoline engines are less efficient than diesel engines, but they are also less expensive to purchase and maintain. Gasoline engines are more common in light-duty trucks, such as pickup trucks and SUVs.
The type of combustion engine that a truck uses depends on a number of factors, including the size of the truck, the intended use of the truck, and the budget of the purchaser.