the 1st number is viscosity ... 2nd number is temparature rating
eg. 10-40 vs 0-30 .... means the 1st one can take more heat but is thicker than the 2nd one
understand boh ?? both oso got pros and cons one depending on your usage ...
i use 10-40 in both the cars in my house ...
if your engine makan minyak hitam ... i advise use 20-50 cheapest grade one .. hehehe
got one sohai using myvi (1 of my mechs customer) that fler pandai2 put 0/40 oil... engine lost power, no pressure, kabcai also tapau him...moral - dont so lanci put ZERO vis oils and show off that u are using racing oils