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  • The Science of Multigrade Oils
  • The Four Types of Wear
  • Carry That Weight
  • New Products Meet the Moment
  • Understanding Oil Viscosity
  • Why Do Motorists Change Oil in the Spring and Fall?
  • Should I Use a Lighter Winter Oil Weight? Play Video
  • How to Read a Gear Oil Viscosity Chart
  • 5W-20 vs 5W-30 vs 10W-30: What’s the Difference?
  • What Happens if I Use A Thicker Oil in My Engine?
  • AMSOIL Performance Testing

    Laboratory tested and proven on the road.

    See how AMSOIL products perform in the lab and in the field.

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