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  • Two New Drivetrain Products
  • Service Marine Lower Units to Prevent Water Damage
  • Classic Car and Truck Maintenance Tips
  • How Often Should I Change Differential Fluid?
  • 8 Overlooked Vehicle-Maintenance Services
  • What is a Limited-Slip Differential (and What Type of Gear Lube Should I Use)?
  • More AMSOIL Products Available in the Award-Winning Easy-Pack
  • Should I Change Fluid in a Filled-for-Life Transmission? Play Video
  • The New SEVERE GEAR Easy-Pack Makes Changing Gear Oil Easy Play Video
  • What Does Oil Viscosity Mean

    Oil viscosity is the measure of its resistance to flow. How quickly or slowly motor oil flows affects how well it protects your engine.

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