Signature Series 5W-50 Synthetic Motor Oil AMSOIL Signature Series Synthetic Motor Oil is engineered to outperform conventional and synthetic motor oils. It combines industry-premier synthetic technology with AMSOIL premium additives in a unique formulation that exceeds the higher performance demands of modern engines. Signature Series delivers the performance and value upon which the AMSOIL reputation is built. The culmination of more than 40 years of expertise, its exclusive formulation raises the bar for motor oil performance. AMSOIL, the leader in automotive synthetic lubrication, produced the world's first API-qualified synthetic motor oil in 1972. Trust the extensive experience of AMSOIL, the First in Synthetics®, to do the best job protecting your engine.

  35 lb. Pail
  120 lb. drum
  415 lb. drum
  Case, 40-14½ oz. cartridges


Base Oil PropertiesLubriplate Clear Plex 2
Temperature Service Range (ºC)-50 to 150
Viscosity (ASTM D445) @ 25ºC500
Viscosity Index (ASTM D2270)>300
Flash Point (ºC) (ASTM D92)>310
Pour Point (ºC) (ASTM D97)-55
Grease PropertiesLubriplate Clear Plex 2
NLGI Grade3
Penetration (ASTM D217) Worked/Unworked240/230
Dropping Point (ºC) (ASTM D2265)>260

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