Fuel consumption when driving with a trailer certainly increases. And it depends on several parameters.
1. Engine volume of a towing vehicle
The smaller the engine, the greater the fuel consumption. The greater the volume of the engine, and accordingly the torque, the less the engine notices the increased load on it.
Air resistance is also an important indicator. The larger the size, the greater the resilience. The greater the resistance - the greater the fuel consumption. A significant deterioration in aerodynamics is observed when a low car pulls a high caravan. In this case, a special spoiler will help improve the aerodynamics of the train
mounted on the car-tractor.
The mass of the trailer, which has to be pulled apart from the car, makes the engine work in an enhanced mode with increased fuel consumption. The greater the mass, the greater the expense.
4. Acceleration and maximum speed
When driving with a caravan, you should forget about fast acceleration, sudden braking and high speed. Everything needs to be done smoothly. The increased mass and the worst aerodynamics make the engine work in an enhanced mode with increased fuel consumption. Sharp acceleration and high speed further increase the load on the engine, and as a result, fuel consumption. Of course on small-displacement engines it is much more noticeable than on powerful multi-engine ones.
And now to the numbers. For example, the fuel consumption on the highway of a Toyota Rav4 with a two-liter gasoline engine is 10 l./100 km. Coupled with a caravan, the maximum displaced mass of 1300 kg., Fuel consumption increases to 14 l./100 km. with an average speed of 80-90 km / h. We get that fuel consumption with a caravan increases by 4 l / 100 km. If you take a lower car, for example, Audi A4 with a similar engine, the fuel consumption increases by 6 liters per 100 km.
Conclusion. The bigger and more powerful the car, the less you will notice the effect of the trailer on fuel consumption and engine traction capabilities. On the contrary, if you have a small car, not even a large caravan will make you think about the correctness of the choice of tractor.