How many km per liter does a truck get?

Have you noticed your truck is using too much diesel and do not know why? Fuel is one of the largest operating costs, and any waste can directly affect the company’s finances.

Increased consumption can be related to mechanical problems, drivers’ driving styles or even maintenance failures — and, unless resolved, the loss only grows.

Some signs help identify this problem, and a few simple changes can save diesel and optimize the operation.

In this guide, we will answer three essential questions:

• What is a truck’s average diesel consumption?
• How can you tell if a truck is using more diesel than it should?
• How can you make a truck more fuel-efficient?

What is a truck’s average diesel consumption?

A truck’s average diesel consumption varies with several factors, such as vehicle model, load weight, route type and driving style. However, a general average can help you understand whether consumption is within expectations.

Lighter trucks usually travel between 6 and 8 km per liter, while medium models get between 4 and 6 km/l. Heavier trucks carrying larger loads can consume more, traveling between 2 and 4 km/l.

To understand whether there is waste, it is essential to calculate truck fuel consumption regularly. Use the following formula:

Consumption (km/l) = Mileage covered ÷ Liters of diesel added during refueling

If the recorded figure is well below the expected average, this can indicate fuel waste in the operation.

How can you tell if a truck is using more diesel than it should?

If fleet fuel consumption is high, it is important to investigate possible reasons. Some signs can indicate the truck is using too much diesel, and identifying them early helps avoid waste and reduce costs.

You should investigate:

• Have kilometers per liter dropped? If the truck used to get 4 km/l and now gets only 3 km/l, something is wrong. Ideally, track this indicator regularly to notice unexpected variations.
• Does the truck emit black smoke? Excessive black smoke can indicate irregular fuel combustion caused by dirty filters, electronic injection faults or engine problems.
• Has the engine lost power? If the truck needs more acceleration to maintain speed or struggles uphill, it may be consuming more diesel than necessary.
• Are the tires improperly calibrated? Driving with underinflated or misaligned tires increases rolling resistance, demanding more engine effort and increasing fuel consumption.
• Does the truck spend a lot of time idling? If the vehicle remains stationary with the engine running for long periods, diesel is being burned unnecessarily. This is one of the biggest sources of waste in the operation.
• Does the driver have inefficient driving habits? Harsh acceleration, excessive braking and incorrect gear changes increase consumption. Untrained drivers can be one of the main factors behind higher diesel use.
• Is the load poorly distributed? If the load is not positioned properly, the truck may need more effort to move, directly affecting fuel consumption.

How can you make a truck more fuel-efficient?

After identifying a truck that uses too much diesel, the next step is to correct the problem. Changes to maintenance and operations can reduce fuel consumption and bring major fleet savings.

Here are some of the best practices to make a truck more fuel-efficient:

Track fuel consumption regularly

Tracking diesel consumption per kilometer traveled is essential to identify variations. Use a control spreadsheet or a refueling management system to record data and act quickly if consumption deviates from the norm.

Perform preventive maintenance

Dirty air and fuel filters, worn injectors and overdue lubricating oil changes can increase consumption. Following a maintenance schedule avoids these problems and keeps the engine efficient.

Train drivers for more fuel-efficient driving

The way a truck is driven directly affects diesel consumption. Good practices include avoiding harsh acceleration and braking, shifting gears at the correct engine speed and using engine braking to reduce consumption downhill.

Keep tires calibrated

Tires with pressure below the recommended level increase rolling resistance, requiring more engine effort. Tire calibration should be performed weekly to avoid waste.

Plan more efficient routes

Avoiding stretches with many hills, congestion or poor roads can reduce trip time and fuel consumption. Route planning systems help choose the best routes.

Use technology to support savings

Telemetry and refueling management systems allow you to monitor each truck’s consumption, identify drivers with inefficient habits and optimize the operation.

Another technology that can generate savings is a tire management system. Precise control of tire calibration and wear reduces rolling resistance, making the truck more efficient.

A Prolog success story showed that, after implementing the system, MC Transportes’ fleet managed to reduce fuel consumption by 4%, simply by improving fleet tire management.

Now that you know how to identify and reduce excessive diesel consumption, how about organizing this information better and improving fleet management?

If you identify a truck using too much diesel, it is a clear sign you need to optimize your controls.

For this, we have the ideal tool you can start using: download our free fuel control spreadsheet (in Portuguese) and track your trucks’ consumption practically and efficiently.