How modern lubricants protect vehicles of today and tomorrow
For more on engine oils and lubricants:
What you'll learn:
- The components of upcoming HD engine oil, including PC-12 oils
- How base oils, additives, and viscosity modifiers interact to protect engines
New performance categories are impacting engine oil formulations like never before. Driven by a continued effort in the auto industry to better enable cutting-edge engine hardware while reducing emissions, today’s engine oils are more technologically advanced than they have ever been.
Currently, the passenger car world is preparing for the arrival of ILSAC GF-7, scheduled for first license on March 31, 2025. Meanwhile, the heavy-duty space is busy anticipating new details around Proposed Category 12 (PC-12), which will be the next generation of HD technology for commercial vehicle diesel engines.
For fleet owners and operators, your choice of engine oil is a critical part of your overall operations. The right choice can propel your vehicles to meet their full potential and achieve operational efficiencies—and it’s worth knowing what exactly goes into top-tier performance. This article will explore the role of base oils, performance additives, and viscosity modifiers, and how they work together to create a finished product you can trust.
What goes into a heavy-duty engine oil?
PC-12-compliant engine oil technology is under development now, and it’s expected to be licensed for use in early 2027. In short, this next generation of engine oils will help deliver improved oxidation performance, stronger wear protection, improved diesel particulate filter performance, and improved fuel economy contributions for heavy-duty trucks. GF-7 products for passenger cars meet different criteria but likewise must deliver elevated performance across several key areas, particularly fuel economy.
How can engine oil meet these new standards? First, it can be helpful to understand what all goes into your bottle of oil. Formulations are composed of three primary component parts:
- Base oil: The base oil is the carrier fluid and delivers basic performance benefits. It makes up the majority of the formulation and is a critical building block for formulating a high-quality lubricant.
- Additive: This is the key performance enabler, allowing the finished product to meet operational requirements when in use.
- Viscosity modifier and pour point depressant: This component ensures the final product will deliver consistent flow across a broad range of operational temperatures and climates.
These components complement each other to create optimized performance that will meet new performance specifications. But there are certain complexities here that engine oil formulators must account for.
For example, base oil availability and pricing can be inconsistent, and access to the highest-quality options is not always a guarantee—and that can pose a formulation challenge. Lower-tier base stocks may not always be adequate for formulating finished fluids to meet today’s elevated standards, like those of GF-7 and PC-12. However, by formulating with higher-performing additive technology, engine oil producers can meet the required performance standards with a range of available base stocks.
Elsewhere, elevated additive performance can enable formulators to utilize viscosity modifiers (VMs) that help maximize engine durability while achieving the necessary fuel economy requirements of new specifications. Because most oil marketers produce both passenger car lubricants and heavy-duty lubricants for diesel trucks, it’s typical to source two separate VM products for each product line. Heavy-duty lubricants typically require VMs that meet a shear stability index (SSI) of 25. Comparatively, passenger car lubricant formulations will utilize VMs with an SSI of 35. A higher SSI, indicating greater shear, helps to enable the final product to deliver higher fuel economy gains at the slight compromise of engine protection and durability.
But optimized additive technology can change those considerations. Top-tier additives enable the final product to achieve those same fuel economy gains required by modern performance categories, while simultaneously allowing formulators to choose VMs with lesser shear (25 SSI). This enables formulators to accept no compromises when it comes to protection and durability while delivering meaningful fuel economy contributions.
Selecting high-performance engine oils
New engine hardware, developed to become more efficient than ever before, requires compatible lubricant technology that can help those engines meet their full potential. Technologically advanced, robust formulations that meet modern performance categories can deliver true real-world benefits.
Procuring engine oil is essential to heavy-duty fleet operations. And armed with the knowledge of what may differentiate one product from the next, operators have the opportunity to select an option that can deliver some real benefits for your business.
How heavy-duty additives deliver longevity and protection
Additive technology has long played an important role in protecting heavy-duty diesel engines. Today, engine technology is growing more advanced to lower emissions, creating more severe operating conditions. Meanwhile, fleet owners and operators want to get as many miles from their trucks as possible while minimizing maintenance needs and their associated costs.
Considering these circumstances, high-performance additive technology is more important than ever before. While base oils provide a baseline of performance across these areas, it is the additive that elevates performance to the levels required by modern specifications like we will see in PC-12.
For example, modern heavy-duty oil additives are designed to prevent a number of challenges, including:
- Oil oxidation
- Viscosity loss due to shear
- Oil aeration
- Catalyst poisoning
- Particulate filter blocking
- Engine wear
- Piston deposits
- Degradation of low- and high-temperature properties
- Soot-related viscosity increase
Taken cumulatively, these attributes mean that today’s high-performance additive technology is truly enabling modern, cutting-edge heavy-duty hardware to meet its full potential.
About the Author
Padu Sreenivas
Product Manager, Lubrizol
Padu Sreenivas is Product Manager at The Lubrizol Corporation and manages Lubrizol’s North American passenger car motor oil business. He has over 25 years of industry experience and has held numerous positions in technology, testing and commercial roles globally.