How to detect fuel theft in your fleet

G.D.E Corp · 14 October 2026 · 5 min read

Fuel is one of a fleet's biggest costs and one of the hardest to watch. Litres disappear a little at a time, the receipts look fine, and consumption is just "a bit high". Here is how fuel goes missing, which signs give it away, and how a tracking system shows the theft.

How fuel goes missing

• Siphoning from the tank while parked. Part of the fuel is drained while the vehicle stands with the engine off.
• Fuel that never reaches the tank. The receipt shows one amount, but less went into the tank; the rest went into a jerrycan or another vehicle.
• Padded mileage. The trip sheet shows more kilometres than the vehicle actually drove, and fuel is written off against them.
• Unauthorised trips. The vehicle works for the driver: driving a taxi after hours, personal use of the company vehicle. You pay for the fuel.
• Long idling. The engine runs for hours while parked. It is not theft, but it is still your money.

Signs you can see without a system

• A vehicle burns more than identical vehicles on the same routes.
• Consumption went up although routes and loads stayed the same.
• Receipts and mileage do not match: lots of refuelling, few kilometres.
• Consumption on the same vehicle changed noticeably with a new driver.

But a sign is not proof. A driver always has an explanation: traffic, heavy loads, an old vehicle. Without data you cannot win that argument.

What GPS tracking shows

The tracker reports where the vehicle is, how fast it is going and whether the engine is running. A fuel level sensor in the tank adds the key part: how much fuel is in the tank at every moment. Together they form a chart on which theft is obvious at a glance.

• A refill is a sharp rise in the level. You see when and where it happened and how many litres actually went into the tank. All that is left is to check it against the receipt.
• Siphoning is the level falling while the vehicle stands with the engine off. Normal consumption never looks like that: fuel is used while driving, and gradually.
• Disconnecting the sensor is recorded too. An attempt to fool the tracking ends up in the report by itself.

With a fuel level sensor and without one

With a sensor fuel is visible to the litre: every refill and every theft on the chart, with place and time.

Without a sensor consumption is calculated from norms and mileage. That is less precise, but noticeably cheaper. You will not see siphoning while parked, but you will see real mileage, unauthorised trips and idling, and that is extra fuel too.

Reports that help

Our MaxTrack software has four fuel reports:

• Fuel report.
• Refills and siphoning.
• Fuel chart report: fuel level, speed and ignition on one chart, zoomable from an hour to a week.
• Fuel chart with mileage.

Reports export to Excel and PDF, both for accounting and for the talk with the driver. You can also have them emailed on a schedule.

What to do once theft is confirmed

1. Save the report for the period as Excel or PDF.
2. Check the refills on the chart against the receipts.
3. Show the chart to the driver. There is nothing to prove and no one to argue with: the report opens in two clicks.

FAQ