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Why are API FA-4 diesel oils not backward-compatible?
Answer: FA-4 oils feature lower viscosity grades and are designed to help next-generation diesel engines maximize fuel economy without sacrificing engine protection. These oils have limited backward-compatibility because some older engines were not designed to operate with lower viscosity grades. It's up to each engine OEM to determine if FA-4 oils can be used in its engines. Check the owner’s manual or with the OEM for specific recommendations.
Answer: FA-4 oils feature lower viscosity grades and are designed to help next-generation diesel engines maximize fuel economy without sacrificing engine protection. These oils have limited backward-compatibility because some older engines were not designed to operate with lower viscosity grades. It's up to each engine OEM to determine if FA-4 oils can be used in its engines. Check the owner’s manual or with the OEM for specific recommendations.
AMSOIL Diesel Motor Oils
AMSOIL synthetic diesel oils offer superior protection and performance over conventional petroleum-based oils. They are designed to extend the life of your engine by providing outstanding wear protection, cleaning power, and overall performance.
AMSOIL synthetic diesel oils are formulated with high-quality base oils and advanced additives. They provide superior protection against wear, corrosion, deposits, and oil degradation. They also deliver outstanding cleaning power, thermal stability, and fuel economy. AMSOIL synthetic diesel oils are available in a variety of formulations to meet the needs of different engines and operating conditions.
AMSOIL synthetic diesel oils are formulated with high-quality base oils and advanced additives. They provide superior protection against wear, corrosion, deposits, and oil degradation. They also deliver outstanding cleaning power, thermal stability, and fuel economy. AMSOIL synthetic diesel oils are available in a variety of formulations to meet the needs of different engines and operating conditions.
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Can diesel oils be used in gasoline engines?
It depends; some AMSOIL synthetic diesel oils carry gasoline specifications. Check the product data bulletin for specific product and drain interval recommendations.
It depends; some AMSOIL synthetic diesel oils carry gasoline specifications. Check the product data bulletin for specific product and drain interval recommendations.
Can I switch from API CJ-4 or CI-4+ diesel oil to API CK-4 diesel oil?
Yes, CK-4 oils are backwards-compatible, meaning they can be used in older diesel engines. CK-4 oils are designed as direct replacements for prior-generation oils, including CJ-4 and CI-4+ oils.
Yes, CK-4 oils are backwards-compatible, meaning they can be used in older diesel engines. CK-4 oils are designed as direct replacements for prior-generation oils, including CJ-4 and CI-4+ oils.
Does AMSOIL offer diesel oils for equipment calling for the API CK-4 specification?
Yes. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil and AMSOIL Heavy-Duty Synthetic Diesel Oil are recommended for diesel applications calling for the API CK-4 specification.
Yes. AMSOIL Signature Series Max-Duty Synthetic Diesel Oil and AMSOIL Heavy-Duty Synthetic Diesel Oil are recommended for diesel applications calling for the API CK-4 specification.
What is the difference between AMSOIL 5W-40 and 15W-40 diesel oil?
AMSOIL 5W-40 and 15W-40 diesel oils are multi-grade oils, meaning they provide good performance in high and low temperatures. AMSOIL 5W-40 and 15W-40 both behave like SAE 40 oils in high temperatures; however, the 5W-40 is thinner than the 15W-40 at start-up and at cold temperatures.
AMSOIL 5W-40 and 15W-40 diesel oils are multi-grade oils, meaning they provide good performance in high and low temperatures. AMSOIL 5W-40 and 15W-40 both behave like SAE 40 oils in high temperatures; however, the 5W-40 is thinner than the 15W-40 at start-up and at cold temperatures.
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