What is the best practice when adding oil to an engine?

What is the best practice when adding oil to an engine?

• A. Use the same type of oil that was previously used
• B. Use any available oil
• C. Use the lowest viscosity
• D. Mix oils to save cost

Answer: (A)

When adding oil, use the same type and viscosity as what is already in the engine. Keeping the oil specification consistent preserves the lubrication film strength and the additive package, so you don’t introduce incompatible additives, changes in viscosity, or unpredictable behavior that can affect oil pressure and wear, especially during starting and high-load operation. This is why the best practice is to top up with the same oil grade that’s in the engine, and to refer to the manual for the exact spec. Using any available oil, choosing the lowest viscosity, or mixing different oils can alter protection and performance, potentially causing engine wear or other issues.

When adding oil, use the same type and viscosity as what is already in the engine. Keeping the oil specification consistent preserves the lubrication film strength and the additive package, so you don’t introduce incompatible additives, changes in viscosity, or unpredictable behavior that can affect oil pressure and wear, especially during starting and high-load operation. This is why the best practice is to top up with the same oil grade that’s in the engine, and to refer to the manual for the exact spec. Using any available oil, choosing the lowest viscosity, or mixing different oils can alter protection and performance, potentially causing engine wear or other issues.