1. Driver training & driving style
The driver remains the single biggest factor in fuel consumption. Anticipatory driving, consistent use of cruise control, shifting up early and avoiding unnecessary idling typically reduce consumption in training programs by 5–10 % immediately after the course. The catch: without regular refreshers and accompanying monitoring, the effect tends to flatten out to 2–5 %. Driver training works best in combination with telematics (point 4), which keeps driving behavior visible on a lasting basis.
2. Tire pressure & rolling resistance
Just 1 bar of under-inflation noticeably increases rolling resistance. Correctly set tire pressure delivers 1–3 % savings depending on the starting condition, low-rolling-resistance tires an additional 1–2 %. The measure costs almost nothing but requires discipline: tire pressure belongs in the weekly routine or – better still – in an automatic tire pressure monitoring system (TPMS).
3. Aerodynamics
From around 80 km/h, air resistance dominates energy demand. Roof spoilers, side skirts, trailer tail devices and closing the gap between tractor and trailer together deliver 3–8 % in long-haul operation. In distribution traffic with low speeds the effect is significantly smaller – here the investment often does not pay off. Acquisition costs are in the low four-figure range per vehicle, depending on scope.
4. Telematics & route planning
Telematics systems make consumption, idle times and driving behavior transparent per vehicle and driver. Combined with optimized route and tour planning (fewer empty kilometers, avoiding congestion), 2–5 % is realistic. The real value lies in permanence: telematics prevents the effects of other measures (especially driver training) from fading again. Running costs: typically €10–30 per vehicle and month.
5. Maintenance & vehicle condition
Clogged air filters, aged engine oil, dragging brakes or misaligned axle geometry quickly add up to 1–5 % extra consumption. A consistent maintenance schedule is not a "saving measure" in the narrow sense, but the precondition for all other measures to have any effect at all. Added benefit: fewer unplanned downtimes.
6. Fuel optimization with a retrofit system
Retrofit fuel optimization systems – such as the Fuel Eco Tech (FET) system – are integrated into the fuel line and improve combustion without intervening in the engine management. The advantage over behavior-based measures: the effect does not depend on the driver's day-to-day form and applies on every trip.
Published measurements exist for the savings of the FET system: in the standardized laboratory test (WLTC cycle, diesel), an average of up to 6 % consumption reduction was measured, and up to 15 % in constant-speed runs – the typical profile in long-haul transport. A documented field test on a Unimog showed around 10.9 % less consumption per operating hour in winter operation. Details and test reports: News & laboratory test and real-world references.
Important for an honest assessment: the actual saving depends on the driving profile – steady motorway and long-distance runs benefit the most, pure stop-and-go traffic less so. Whether the investment pays off can be estimated in a minute with the payback calculator.
7. Fleet renewal
A new vehicle generation typically consumes 3–6 % less than the previous generation; LNG, HVO or electric trucks change the cost calculation fundamentally. This is the most effective but also by far the most expensive lever – and for existing fleets with several years of remaining service life, rarely feasible in the short term. For the meantime, measures 1–6 are the realistic answer.
Comparison table: all measures at a glance
| Measure | Typical savings | Investment | Effect |
|---|---|---|---|
| Driver training | 2–10 % | Low | Fades without monitoring |
| Tire pressure & low-rolling-resistance tires | 1–3 % | Very low | Lasting with discipline |
| Aerodynamics | 3–8 % | Medium | Lasting, especially long-haul |
| Telematics & route planning | 2–5 % | Low–medium (ongoing) | Lasting, stabilizes other measures |
| Maintenance | 1–5 % | Low (ongoing) | Precondition for everything else |
| Fuel optimization (e.g. FET) | up to 6 % (WLTC), up to 15 % (constant speed)* | Medium, one-off | Lasting, driver-independent |
| Fleet renewal | 3–6 % per generation | Very high | Lasting |
* Figures from a published laboratory test (WLTC and constant-speed cycles, diesel) and a documented field test; see test reports. All other figures are typical industry values – the actual saving depends on driving profile, vehicle condition and starting point.
Conclusion: combine measures instead of relying on one
No single measure solves the cost problem alone – but they add up. A realistic strategy for existing fleets: maintenance and tire pressure as the foundation, telematics for transparency, driver training for behavior, and a technical measure such as fuel optimization for the driver-independent base. In total, double-digit percentage savings are achievable without buying a single new vehicle.