The role of lubricants in fuel economy

By Karl Rudman, Business Development Manager, Petro-Canada Europe

Fleet owners and managers are always looking for ways to improve the efficiency, reliability and performance of their fleets, to save money on the bottom line and also be compliant with ever-tightening environmental legislation.

Policymakers have certainly set their sights on lowering carbon emissions in recent years and evolving legislation has had a big impact on the heavy duty diesel engine market. Heavy goods vehicle Original Equipment Manufacturers (HGV OEMs) have made significant progress in cutting vehicle emissions. However, there is still some way to go. According to the European Commission, CO2 emissions from HGVs rose by 36% between 1990 and 2010, mainly due to increasing road freight traffic. Projections indicate that, without policy action, total HGV emissions would still be close to current levels in 2030 and beyond. The new Euro VI standard has been implemented which aims to tackle this challenge head on with the introduction of more stringent emissions limits for both commercial vehicles and passenger cars.

Whilst emissions legislation has been tightening, fuel price volatility has also created an increased appetite among fleet operators for more fuel efficient vehicles. With approximately 35% of operational costs for fleet operators attributed to fuel, it is a large expense; so even small decreases in fuel consumption can have a significant impact on business bottom lines.

OEMs are responding to both legislative developments and end user demands by designing smaller, more efficient HGV engines which run at higher operating temperatures and utilise the latest surface materials to reduce friction in engines.

But engine design is not the only way to improve fuel efficiency of HGVs. Lubricants can also contribute directly by minimising frictional losses between moving components of the engine and also reducing pumping and spinning losses, meaning the work required to move a component through the lubricant. To this end, the industry has seen a growing trend towards lower viscosity engine oils.

By running at higher temperatures, newer engine designs can stress conventional lubricants and accelerate the rate of oil oxidation and degradation. The end result is that the ability of the oil to protect engine components from wear and heat dissipation worsens and the frequency of oil changes is increased – leading to more vehicle downtime and higher maintenance costs. Clearly, this can very quickly negate any cost benefit associated with improved fuel economy.

To address these new technical challenges, next generation engine oils are emerging which are designed to provide greater durability and meet the needs of current and future engine hardware.

Petro-Canada Lubricants has taken this challenge head on, which has resulted in the launch of new DURON™ Next Generation heavy duty diesel engine oils that couple the latest innovations in oil additive technology with some of the purest base oils to deliver improved oxidation resistance (reducing long term oil degradation), shear stability (known as the ability to maintain stay-in-grade oil viscosity properties under high stress conditions) and aeration control (which is critical in the lubrication of modern high temperature engines). Taken together, these lubricant design improvements provide enhanced performance, greater hardware protection, and may reduce vehicle downtime.

Our DURON Next Generation products are the culmination of considerable research into lowering engine oil viscosity while maintaining their ability to withstand a high-shear engine environment –offering the opportunity for fewer oil changes, extended drain potential, and to provide engine protection for longer periods.

DURON Next Generation engine oils have been field tested in Canada’s harshest environments and most extreme temperatures, so fleet operators can be assured that they will provide optimum efficiency wherever and however they are being used. This no-compromise approach means fleets are ready to face anything and stay on the road at all times.

Of course, improving fuel economy doesn’t end with changes to engine design or the engine oil used. OEMs and fleet owners need to consider the overall driveline efficiency of their vehicles – from the choice of tyres and wheels, to the driveshaft installation angle and transmission design, right down to the choice of lubricant used for a particular operating condition – there are many individual components to the driveline that have an impact on fuel economy.

Ultimately, each part of the driveline can impact on the efficiency of the system as a whole and the subsequent fuel economy achieved. Small improvements, or marginal gains, at each stage of the driveline can add up to a big fuel economy improvement overall.

There is a complex mix of factors behind fuel economy – but the type and viscosity grade of lubricant used can certainly play a part. The early adoption of lubricants that promote fuel economy creates an opportunity for the proactive fleet manager to both reduce their fuel costs and improve the performance of their fleets and for the wider industry to meet its ambitious reduction targets.

Fleet operators would be advised to discuss with their OEM and consult with them for specific guidance regarding the recommended viscosity grade for their engines and which sub-category will be best suited for their business.

Further information about DURON Next Generation is available online.