![From my understanding, the second number is the viscosity at running temp, so how come 5W-30 and 10W-30 don't go up to the same temperature? : r/MechanicAdvice From my understanding, the second number is the viscosity at running temp, so how come 5W-30 and 10W-30 don't go up to the same temperature? : r/MechanicAdvice](https://preview.redd.it/gddasdse4mb81.png?auto=webp&s=ccc81aa43eea55b5b5e9382ba3bf10b05d860548)
From my understanding, the second number is the viscosity at running temp, so how come 5W-30 and 10W-30 don't go up to the same temperature? : r/MechanicAdvice
Are multigrade oils really necessary in regions with hot climates where temperatures hardly go below 20 C? If the OEM recommends 15w40 can I just use a mono grade SAE 40? - Quora
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