Breaking the cycle: How lubricant technology is engineered to help reduce heavy-duty trucking’s emissions

With fuel costs comprising approximately 55% of the total cost of ownership (TCO), any decision that can improve fuel efficiency will ultimately improve a fleet’s competitiveness.¹ Or, put another way, any component that is overlooked or undervalued as part of this equation can, over time, become a huge missed opportunity. And with margins for error shrinking, only those who identify and act quickly on these developments are likely to succeed.

Why lubrication is a critical fleet component

Lubrication is a perfect case in point. Traditionally viewed simply as an operational ‘must have’ rather than an operational ‘value add,’ your choice of lubricant can instantly affect fuel economy. However, switching from viewing lubrication as a financial outlay to seeing it as a fuel efficiency opportunity can help us understand the science behind this impact.

The energy required for your engine to push lubricant through the system has a substantial say in how efficient your vehicle’s total operation can be. For example, if this process is difficult for the engine, less energy is available to drive the truck along the road, increasing fuel consumption and the associated emissions. On the other hand, if the engine is not forced to expend so much energy in pushing the lubricant throughout, then the opposite is true.

So, what makes a lubricant easier for the engine to deal with? The short answer is viscosity – the lubricant’s resistance to flow. Ultimately, the thicker the fluid, the greater resistance experienced within the system. While a lubricant also needs to perform other functions – not just reducing friction and protecting from component wear – generally, the thinner it is, the greater its ability to improve fuel economy.

Balancing the emissions equation

All of this has a significant impact on your fleet’s emissions output. An increasingly important consideration given that while heavy-duty trucking makes up just 1% of total fleet vehicles on the road worldwide, it represents 25% of the emissions that come from the road.² Again, it’s important to fully understand the facts behind how these emissions are produced and measured to manage them best moving forward.

Trucks emit both carbon dioxide (CO₂) and tailpipe emissions (particulate matter (PM) and nitrogen oxides (NOx)). While CO₂ emissions often seem to take prominence in conversations surrounding decarbonization, the industry-wide emission standards measure the latter – PM and NOx–. 

Meanwhile, a vehicle’s CO₂ emissions are measured through a relatively complex set of equations that consider the amount of fuel consumed by a commercial vehicle during different operating parameters. Ultimately, the amount of CO₂ emitted by a truck is dictated by its overall efficiency, proving the importance of lubricant choice alongside other operational decisions that have the potential to affect this output.

Not all oils are created equal.

Lubricants are a core component of vehicle design that can help reduce fuel consumption while protecting components. If a lubricant can provide even a 1% efficiency benefit through lower viscosity, it can help OEMs meet their fuel efficiency requirements.³ As a result, OEMs have a clear incentive to make lubrication decisions that will support wider environmental legislation.

This is why OEMs are increasingly moving towards even lower viscosity oils, having realized the fuel consumption benefits they can offer. As these shifts become more widespread across the sector, engines and other driveline components – such as transmissions and axles – eventually are redesigned to facilitate the new, more beneficial oil technology.

With lubrication as a critical element of engine and component development, it becomes more important than ever for lubricant suppliers to develop products that meet the highest specifications – creating a virtuous cycle of product and technology development.

However, this doesn’t mean every lubricant will rise to the same standard. While it is relatively easy to make a low viscosity oil, it is more challenging to make one that also provides excellent durability throughout its lifetime, which can be proven under field trial conditions. Therefore, only the most effective and efficient lubricants are recommended by leading manufacturers.

The benefits of following the formula

When OEMs make their trucks more efficient by design, shaping components around industry-leading technologies – such as low viscosity lubrication – fleet operators should take note. After all, if trucks are designed this way to meet efficiency standards, it would be remiss of operators to overlook the potential benefits they can reap by following these recommendations. Many fleets realize the potential that lubricants hold for their business, creating a professionally run maintenance program with the latest lubricant technology at its core. 

Shell Rotella® offers a complete portfolio of synthetic and synthetic blend heavy duty engine oils that offer a wide range of specifications and approvals from many of the world’s leading engine manufacturers, making them an excellent choice for on-highway fleets. This includes Shell Rotella® T6 Full Synthetic engine oils which provide protection that can save money with enhanced fuel economy capability and Shell Rotella® T5 Synthetic Blend products which protect against wear, deposits, and oil breakdown and provide better low temperature flow. The result is that the whole powertrain is subsequently working towards reducing the fleet's TCO.

Making the switch to full synthetic or synthetic blend engine oil is easy – it simply requires you to change your lubricants during regular service. There is no costly driver training or performance measurement, just the lower drag of the lubricant in your vehicle, allowing for greater fuel economy and strong engine protection. These engine oils can also help reduce emissions and vehicle downtime.

Disclaimers

_{¹North American Council for Freight Efficiency. “2022 Annual Fleet Fuel Study (PDF) (PDF)}

.” 2022.

_{² Amina Hamidi and Enrique Meroño. “How to decarbonize heavy-duty transport and make it affordable}

.” World Economic Forum. 16 August, 2021.