What Brand of Engine Oil is Best for Subaru?

1 Answers
Archie
07/29/25 11:08pm
Subaru recommends using Mobil Super 2000 5W-30 or Castrol Magnetec 5W-40. Engine oil selection: When choosing engine oil, the primary consideration should be the viscosity index. Speed (based on general driving conditions), engine load level, and temperature (depending on the driving environment) are the three main factors in selecting viscosity. The higher the speed, the lower the viscosity oil you should choose. The higher the load, the higher the viscosity oil you should choose. The higher the temperature, the higher the viscosity oil you should choose. Engine oil quality depends on: Base oil and additives. The quality of the base oil depends on: crude oil source and refining technology, synthetic process technology. Additives mainly include: anti-wear agents - reduce friction and wear, detergents - prevent surface deposits, dispersants - keep insoluble matter suspended, antioxidants - inhibit oxidative decomposition, corrosion inhibitors - prevent metal parts from rusting, friction modifiers - improve friction performance, demulsifiers - separate oil and water, pour point depressants - improve low-temperature fluidity, anti-foam agents - reduce foam (air in oil) formation, viscosity index improvers - improve viscosity-temperature characteristics, EP additives - control wear under extreme load conditions.
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