As hybrid vehicles grow in prominence throughout the North American landscape, some industry stakeholders are seeking to elevate lubricant performance to match their needs. Here's what that means for oil marketers.

Hybrid electric vehicles are a familiar sight to drivers throughout North America. They make up an increasingly large portion of the overall car parc, representing approximately 12% of all light-duty vehicle sales by powertrain as of 2025, according to the U.S. Energy Information Administration.

Considering their consistent rise in popularity, it is important that the lubricants industry considers the unique needs of hybrid vehicles in modern engine oil formulations. And recently, the American Petroleum Institute (API) has made a more formal push to do exactly that.

Earlier this year, API proposed the development of a new performance specification specifically catering to hybrids. Engine oils meeting such a specification would deliver elevated performance in certain areas-including low-temperature wear protection, emulsion retention, and more-compared with conventional engine oils. The specification is intended to see first license by the end of 2025.

It is an unconventional proposal, given that new specification development is typically spurred by OEMs' request. To date, major hybrid OEMs have been satisfied with engine oils that meet the standard performance requirements per ILSAC GF-6 and GF-7.

So, why a hybrid specification now? In this article, we'll explore necessary engine oil performance in hybrid drivetrains, the particulars of the hybrid specification proposal, the potential implications for oil marketers, and why Lubrizol believes that specification developers must remain focused on delivering clear and established value to the marketplace.

How Hybrids Differ from Conventional Drivetrains

In a typical hybrid drivetrain setup, an internal combustion engine (ICE) works in conjunction with a battery-powered electric motor to maximize fuel efficiency and performance. Using a computer-controlled energy management system, the vehicle switches between, or combines, power from the ICE and the motor based on driving conditions.

The ICE in this setup is serviced using typical engine oil. However, because the duty cycle of the ICE differs significantly in a hybrid drivetrain compared to a conventional one, operational conditions can become more challenging for the lubricant.

For example, a hybrid ICE maintains lower operating temperatures while the vehicle is being primarily powered by the electric motor. Hybrids also exhibit more stop/starts than traditional ICE vehicles, meaning temperatures do not reach sustained higher temperatures for extended periods of time.

Because the duty cycle of the engine differs significantly in a hybrid drivetrain, operational conditions can become more challenging for the lubricant.

Because of these conditions, the ICE component may not as effectively burn off condensation that may form during combustion. As such, the lubricant will inevitably experience water ingress during normal operations, which can lead to excessive emulsification of the lubricant and water. In this scenario, the lubricant/water emulsion takes on the characteristics of an undesirable "sludge," and its ability to provide adequate wear and corrosion protection can be compromised.

Elsewhere, lubricants protecting ICE components in hybrids are more likely to experience elevated levels of fuel dilution. When the lubricant becomes excessively diluted, its wear performance can be compromised, leading to premature wear on critical engine components and thus shortening the life of the system.

The Impact of a Hybrid Specification

API's proposed hybrid specification would account for some of these concerns, with a focus on emulsion retention, low temperature wear protection, copper corrosion protection, engine oil gelation and storage, exhaust system compatibility, and, of course, fuel economy. In addition, all other performance requirements will be aligned with ILSAC GF-7/API SQ.

Some in the industry have questioned the specification's urgency and necessity. With ILSAC GF-8 already in development, it stands to reason that the hybrid specification's proposed performance enhancements may simply be rolled into GF-8's requirements. Further, many lubricants available throughout the market today likely already meet the hybrid specification's proposed requirements, and hybrid OEMs have not, to date, expressed dissatisfaction with the availability of oils that best serve hybrids. It will be important that a new specification does not create unnecessary market fragmentation or consumer confusion, and the industry will need to be clear about product performance claims.

It is incumbent upon the lubricant industry to ensure that available products enable a growing diversity of engine architectures throughout the marketplace.

Nevertheless, it is incumbent upon the lubricant industry to ensure that available products enable a growing diversity of engine architectures throughout the marketplace. Lubrizol is committed to supporting oil marketers in successfully executing their go-to-market strategies with high-performance additive science that meets the needs of today's and tomorrow's engine hardware.

Since hybrid vehicles became a common sight on American roadways, we have continuously invested in validating our hybrid solutions, and have logged more than 2 million miles of successful field trial testing. Lubrizol® PV1710-our ILSAC GF-7 additive package—has demonstrated the required performance characteristics of the proposed hybrid specification, and can help you deliver market-ready formulations that go above and beyond.

Learn more about Lubrizol’s solutions for GF-7 and more

Investigación de una nueva especificación para aceites para motores de vehículos híbridos