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All You Need to Know About FA-4 Heavy-Duty Engine Oils

Take a closer look at the benefits of API FA-4 engine oils and bust some of the misconceptions.

by Darryl Purificati, Petro-Canada Lubricants
August 19, 2020
All You Need to Know About FA-4 Heavy-Duty Engine Oils

The benefits surrounding the API FA-4 engine oils and their use in a mixed fleet may also be misunderstood, particularly for the workshop and how they will store, handle, and use two heavy-duty lubricants.

Photo: Petro-Canada Lubricants

4 min to read


API FA-4 heavy-duty engine oils were launched alongside API CK-4 lubricants in December 2016. Offering enhanced fuel economy through lower viscosities, API FA-4 oils have been designed for use in 2017 EPA compliant engines, operating in conjunction with optimized hardware technology to maximize the vehicle’s overall efficiency.

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Here, we take a closer look at the benefits of API FA-4 engine oils and bust some of the misconceptions we’ve been hearing from our customers and other industry sources surrounding the low viscosity lubricant category.

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A Focus on FA-4 Lubricants

API FA-4 engine oils are designed with a lower high-temperature high shear (HTHS) viscosity than their API CK-4 counterparts. This means that when at operating temperatures, these oils flow more quickly through the engine, providing vital lubrication to the internal hardware.

The ease of flow also reduces friction, fuel consumption, and lowers exhaust emissions to improve the overall efficiency of the vehicle. This is particularly important for the newer engines that API FA-4 oils are designed for as they run at higher temperatures, which can stress conventional lubricants and accelerate the oxidation and degradation of the oil.

Designed to deliver greater performance and efficiency for modern engines, API FA-4 lubricants can make a real difference to a fleet’s bottom line by improving the engine’s fuel efficiency. According to industry research, API FA-4 engine oils provide additional fuel savings over API CK-4 of the same grade - up to 1% when comparing an SAE XW-30 with 3.5cP HTHS to an XW-30 with 3.1cP HTHS. 

Common FA-4 Misconceptions

The transition to API FA-4 engine oils has been expectedly slower than the adoption of CK-4 lubricants. API FA-4 engine oils are only compatible with some of the latest Original Equipment Manufacturers (OEMs) engine technologies, so their use is likely to continue to increase gradually over the coming years as newer vehicles enter the market.

For example, factory fill of API FA-4 lubricants in Class 8 Trucks is expected to increase again this year. This gradual transition has coincided with several misconceptions about the protection and benefits that the new oil category offers, as well as the practicalities of using API FA-4 lubricants.

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One widespread myth or misconception is that low viscosity API FA-4 lubricants cannot possibly offer all-year-round protection like their predecessors. This is not the case. Due to their formulation and unique balance of additives, low viscosity API FA-4 engine oils can deliver superior protection for engine hardware, while also flowing more efficiently throughout the engine to offer improvements in fuel economy and enhanced performance in cold startup environments.

API FA-4 licensed products have to go through the same rigorous testing that API CK-4 products have to complete, so they must be designed to protect just as well as the CK-4 oils.

The benefits surrounding the API FA-4 engine oils and their use in a mixed fleet may also be misunderstood, particularly for the workshop and how they will store, handle, and use two heavy-duty lubricants.

By using a color-coded labeling system, the lubricants can be easily differentiated. This not only makes storage, handling, and use easier for technicians, but it also helps reduce the risk of incorrect lubricant use. Seeking expert lubricant support can assist with this process, with the experts sharing their advice to ensure the workshop runs as smoothly and efficiently as possible.

Another common misconception surrounding the use of API FA-4 oils in a mixed fleet is that there will be little benefit to its overall efficiency. It’s important to remember that only by using the API FA-4 engine oil will the engine operate at its optimum efficiency. With the potential for improving fuel efficiency by up to 1%, in an industry where fuel cost is one of the largest outlays for a business, this can make a real difference – even if only half of the fleet vehicles are using the API FA-4 lubricant.

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API FA-4 lubricants maximize the efficiency and performance of modern engine technology while offering tangible operational cost savings for fleet managers. By integrating API FA-4 engine oils into your fleet’s compatible vehicle maintenance program, fleet managers can benefit from the oil’s superior protection and efficiency capabilities.

API FA-4 licensed products have to go through the same rigorous testing that API CK-4 products have to complete, so they must be designed to protect just as well as the CK-4 oils.

Photo: Petro-Canada Lubricants

About the Author: Darryl Purificati is the OEM technical liaison for Petro-Canada Lubricants.

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