AMSOIL Signature Series 0W-40 (AZF) is now recommended for applications that call for the Chrysler MS-A0921 specification.
This specification covers many newer Dodge SRT street-performance vehicles like the Challenger and Charger SRT equipped with the 6.2L Hellcat engine as well as Ram TRX (6.2L) and HD models such as the 2500 and 3500 series trucks equipped with the 6.4L Hemi.

Signature Series 100% Synthetic Motor Oil

• 75% more engine protection against horsepower loss and wear¹
• 50% more cleaning power vs. AMSOIL OE Motor Oil
• Protects turbochargers 72% better than required² by the GM dexos1 Gen 2 specification
• 28% more acid-neutralizing power than Mobil 1³
• Trusted by professional engine builders
• Guaranteed protection for up to 25,000 miles or 1 year

¹Based on independent testing of AMSOIL Signature Series 0W-20, in ASTM D6891 as required by the API SN specification.
²Based on independent testing of AMSOIL Signature Series 5W-30 in the GM turbo coking test.
³Based upon independent testing of Mobil 1 Annual Protection Full Synthetic 5W-30 and AMSOIL Signature Series 5W-30 in ASTM D2896. Oils purchased in July 2020.