heloo,
need to know what is the best engine oil viscosity for us here in east part of the world?? Malaysia.
car running 100k++ km already.

 

Honda recommends 5w20 or 0w20. viscosity rating is based off bearing clearances and ambient temps to put it simply.

 

I would check what is recommended for the particular version that you have. In the usa 5w20 then 0w20 were required but we have "cafe" rules that push the car maker to produce a fleet of cars with better mileage. Looking at the Motul site, in Japan it may be 0W20 but in Europe it might range for 0W20 to 5W30.