Is Brand X motor oil best because my engine shows higher oil pressure?
The viscosity of engine oil has a direct effect on engine oil pressure: Oils with higher viscosity may show higher oil pressure. Therefore, your engine may show higher oil pressure when using a viscosity grade higher than what is recommended. Oil pressure is also affected by temperature. Shortly after start-up, your engine may show higher oil pressure than after the engine has warmed up. You may also notice higher oil pressures after start-up during the winter than during the summer. High quality oils of the same viscosity grade would be expected to give very similar engine oil pressures under similar operating conditions.
