Fleet fuel economy is how efficiently vehicles turn fuel into distance. It is usually expressed as miles per gallon (MPG) or litres per 100 kilometres (L/100km), and it is one of the clearest early signals that something has changed on a route, a vehicle, or a driver, long before it shows up in the total fuel bill.
A Note on Units
MPG is not one number. A US gallon is smaller than a UK (imperial) gallon, so US MPG figures look lower than UK ones for the same vehicle. Much of the world uses L/100km instead, where a lower number is better. When comparing vehicles, always compare like with like, and ideally convert everything to a single measure such as cost per mile.
What Affects Fuel Economy
- Driving style: idling, harsh acceleration, and speed.
- Vehicle condition: tyre pressure, servicing, and load.
- Route and duty cycle: stop-start urban work versus steady motorway miles.
- Data quality: a fill logged against the wrong vehicle instantly distorts its apparent MPG.
Real-World vs Official Figures
Manufacturer economy figures come from standardized tests and rarely match real-world fleet use. What matters is your own measured economy per vehicle, trended over time, not the brochure number.
Why It Matters
A sudden drop in a vehicle's fuel economy is an early warning: a maintenance issue, a route change, a driver behaviour problem, or a fuel transaction that never belonged to that vehicle. Tracked per vehicle, it feeds directly into cost per mile and total cost of ownership.
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How Fleevo Uses Fuel Economy
Fleevo calculates real fuel economy per vehicle from reconciled fuel and telematics data, so a distorted MPG figure points either to a genuine efficiency problem or to a fuel transaction that does not reconcile. See fleet idling costs, how to calculate cost per mile, and Fuel & Energy Management.
Fleet Fuel Economy FAQs
How is fleet fuel economy measured?
As MPG (miles per gallon) or L/100km. For fair comparison across vehicles, convert to a single measure such as cost per mile.
Why do US and UK MPG figures differ?
A US gallon is smaller than a UK imperial gallon, so the same vehicle shows a lower MPG in US units than in UK units.
What causes a sudden drop in fuel economy?
Driving behaviour, tyre or maintenance issues, a route change, or a fuel transaction wrongly attributed to the vehicle. It is a useful early warning worth investigating.
Related: fleet idling costs, fleet cost per mile, and what is fleet fuel management.
