Hi!
Use a good Oil.
Don't look back to history,time pass.
Better Oil can last longer in the engine and have lower friction,more power.
Your engine last longer and burn les - you save surrounding life too and money.
At the present time we have wonderful Oil Mobil1 0w40 - so powerful for cold and very hot weathers.Easy can last for 10 000 mil.
I try picturaize for you this Oil is much more stronger and out perform
many times 20W50 Raising Oil.
Recommended by MB too.

Regards.