How Tyre Pressure Directly Affects HGV Fuel Efficiency

The Science of Rolling Resistance

Every tyre has a rolling resistance coefficient — the energy lost as heat as the tyre deforms and recovers with each rotation. Under-inflated tyres deform more significantly with each rotation cycle, generating more heat and requiring more energy from the engine to maintain speed. Research from Michelin and other leading tyre manufacturers consistently shows that running a 44-tonne artic with all tyres inflated 10 PSI below specification increases fuel consumption by approximately 0.5-1%. Across an annual mileage of 100,000 miles at typical HGV fuel consumption, this represents hundreds of litres of additional diesel per vehicle.

The Fleet-Wide Financial Impact

On a fleet of 20 HGVs each covering 100,000 miles annually, even a 0.5% improvement in fuel economy through correct tyre inflation represents a meaningful annual saving at current diesel prices. When you consider that industry surveys consistently find 20-30% of commercial vehicle tyres operating below recommended pressure at any given time, the financial opportunity from better tyre pressure management is significant. For many fleets, tyre pressure management is the single highest-return fleet management action available.

How to Implement Effective Tyre Pressure Management

Effective tyre pressure management starts with clear standards: know the correct operating pressures for each axle position on each vehicle type in your fleet, and ensure this information is accessible to drivers and workshop staff. Provide drivers with calibrated pressure gauges as part of their vehicle equipment. Train drivers to check pressures cold (before driving) at every journey start. Calibrate workshop air lines and gauges regularly to ensure accuracy. Consider fitting tyre pressure monitoring systems (TPMS) on high-value or high-mileage vehicles for real-time visibility.

Nitrogen Inflation: Is It Worth It for HGV Fleets?

Nitrogen inflation for commercial vehicle tyres has genuine merit. Nitrogen molecules are larger than oxygen molecules, meaning they permeate the tyre casing more slowly — nitrogen-filled tyres lose pressure approximately three times more slowly than air-filled tyres. Nitrogen is also non-combustible and contains no moisture, which reduces the risk of internal rim corrosion and eliminates pressure fluctuations caused by water vapour expansion at operating temperature. For high-mileage or safety-critical vehicles, nitrogen inflation is a worthwhile investment in tyre pressure stability and tyre longevity.