Improving fleet fuel economy will be an ongoing journey, with no end point in sight at the current time. By transitioning to lower viscosity solutions today, a waste fleet can secure fuel economy savings and
reduce carbon emissions.
By Darryl Purificati

Over the past decade, the drive towards improved fuel economy and reduced exhaust and carbon emissions has been evident. In the waste industry, where fuel can represent one of the largest business costs, it is unsurprising that operators and managers are constantly exploring new and innovative methods to secure fuel economy gains.

However, before turning to new technologies, it is important to consider if all aspects of the vehicle are performing optimally, particularly for waste fleets that carry heavy loads and spend a
significant amount of time idling. A vehicle’s lubricants play a key role in this and can help improve engine performance and, therefore, fuel economy.

The Role of Lubricants
Engine oils play an essential role in the protection and performance of the engine and, therefore, the vehicle. As Original Equipment Manufacturers (OEMs) continue to develop their engines, lubricant formulations and technologies have become more advanced to meet the needs of modern engines and the continued focus on improved fuel economy and reduced carbon emissions.

To provide the engine hardware with the crucial protection that it needs while securing fuel economy gains, lubricants have benefitted from improved chemistry while transitioning toward lower viscosity solutions over the past decade.

Lower viscosity engine oils flow faster than heavier viscosity engine oils, requiring less work to move through the engine, so that the engine does not have to work as hard to provide the same level of power. They also reduce drag in the engine, as well as pumping and rotational losses. This enables the engine to run more efficiently, using less fuel to achieve the same output and improve fuel economy.
Put through the same rigorous testing as higher viscosity lubricants to demonstrate their protection capabilities, lower viscosity solutions also benefit from enhanced oxidation resistance, aeration control, and shear stability when compared to the previous generation engine oils.

The Journey Toward Lower Viscosity
The low viscosity journey has accelerated over recent years, with a key milestone being the launch of API CK-4 and FA-4 lubricants in 2016, to meet the needs of modern engines as well as environmental legislation and vehicle emission regulations. These engine oils1 offer superior engine protection, improved engine efficiency, and the potential to safely extend oil drain intervals.*

As the move toward enhanced fuel economy and lower carbon emissions continues, engine architecture is evolving. Engines now have tighter internal clearances, which can work with lower viscosity lubricants to enable proper flow around the engine.

This has resulted in a marked shift in the lubricants that are used in waste fleet engines. For example, traditionally the ‘go-to’ lubricant for the waste and heavy-duty industries was an SAE 15W-40 engine oil, while today SAE 10W-30 lubricants are encountered more often. In fact, SAE 15W-40 lubricants have peaked and are forecast to decline to near 30 percent by 2029. By the same year, SAE 10W-30 is expected to account for approximately 40 percent of the market and SAE 5W-XX could account for up to 10 percent.2

Looking Ahead to API PC-12
The development and introduction of PC-12 will likely accelerate the transition to lower viscosity solutions even more, helping to reduce carbon emissions and improve fuel economy.

The new specification is being developed to help OEMs meet the latest greenhouse gas and fuel mileage regulations issued by the U.S. EPA and the California Air Resources Board (CARB).

While the details of the new specification are yet to be finalized, PC-12 lubricants will be formulated to meet the performance needs of the latest engine and emissions systems technologies. This means that wear protection will be even more important, as will oxidation control, due to engines working harder with increased operating temperatures to help meet new regulation guidelines.

The new category is expected to have two subcategories, including one which takes advantage of lower high temperature high shear (HTHS) oil viscosity (similar to API FA-4). This category will be designed for specific OEM hardware architecture and offer even lighter grades of lubricants (possibly even SAE 0W-20s) that provide wear protection and durability, while further reducing viscous drag to ultimately improve fuel economy.

The new engine lubricants will undergo rigorous testing, similar to their predecessors, so that fleets can be reassured that high-performance qualities have not compromised protection of the engine’s componentry. This will likely see these lubricant categories face new tests developed in line with the latest engine architecture.

Getting Ready for Improved Fuel Economy and Lower Viscosity Lubricants
Improving fleet fuel economy will be an ongoing journey, with no endpoint in sight at the current time. By transitioning to lower viscosity solutions today, a waste fleet can secure fuel economy
savings and reduce carbon emissions while getting ready for the introduction of PC-12. This period can then be used for evaluating the fleet’s make-up and considering the equipment you may want to invest in before PC-12 and its fuel economy-focused lubricants are available. | WA

Darryl Purificati is Sr. Technical Advisor, OEM/Automotive, for Petro-Canada Lubricants. He has 27 years of experience working in the oil and energy sector as a technical advisor. He joined Petro-Canada in 1994 to support its lubricants business and the Petro-Canada Lubricants brand (later acquired by Suncor Energy in 2009) from Ryerson University, where he graduated with a Bachelor of Science (Hon) in Applied Chemistry. In 2017, Petro-Canada Lubricants was acquired by HollyFrontier and in 2022, HollyFrontier and Holly Energy Partners established HF Sinclair, where Darryl continues to provide technical expertise for the Petro-Canada Lubricants brand. He has successfully undertaken various roles including Lubricants Research and Development, OEM Sales, Fuels.Quality and Technical Services. Since 2012, Darryl’s expertise has been used across the industry in his role as industry liaison and technical advisor for OEM and driveline products. Darryl is also widely involved within the industry as an active member of the American Petroleum Institute, ASTM International and the Society of Automobile Engineers. For more information, visit

1. Such as the Petro-Canada Lubricants DURONTM product line.