Most diesel engines have very low diesel fuel consumption rates. Especially as compared to gasoline powered engines of the same size. However, diesel engine efficiency has increased from just a few years ago, due to a number of factors, such as improved formulations, additives and refining practices. However, there are certain types of diesel engines that have higher diesel fuel consumption rates than others.
Higher Displacement Engines
Larger engines, by simple definition are going to have higher diesel fuel consumption rates than smaller engines, because more fuel and air can fit and are needed to produce power. What this means is that the engine in that big rig you passed a mile ago is going to consume more fuel per hour than the engine in the Chevy pickup you passed an hour ago. Your small passenger car diesel engine is thus going to have the lowest diesel fuel consumption rate of the three.
Producing more Power by Turbocharging
Whether gasoline or diesel, an engine equipped with a turbocharger is going to produce more power, because the fuel and air mixture is packed into the combustion chamber under higher pressure. This will also mean a higher rate of diesel fuel consumption. Diesel of a new engine type will have lower diesel consumption rates than older engines, but they will still consume more fuel than a non-turbocharged engine.
Just like with a gasoline powered engine, if you like to drive and accelerate fast, your diesel fuel consumption rate is going to be significantly higher than the rate of fuel consumption of someone who accelerates slowly and drives the speed limit.
Paying attention to these factors listed above will help you maximize your diesel fuel mileage.