Quote Originally Posted by Wh1stl3r2 View Post
Having the same winter numbers only means they should more or less behave the same way during cold starts. The actual oil thickness at operating temps is the 2nd number. Thicker isn't always better, thicker oils get you less fuel economy. Also, with group 1, 2 and 3 oils the bigger the difference between cold and hot numbers, the higher the amount of viscosity improvers. These VI give out eventually and when they do, the oil will behave more like a monograde oil with the hot number viscosity at startup. That's one reason why mineral/semi syn oils should be changed more frequently.
Can I use 10w30 in a hot climate such as here in the philippines ??? I don't want to use mobil semi-synth 10w40 or fully synth 5w30 mainly because my engine is an old Corolla GLi 4afe 1.6 .. I found out that the only 10w30 mineral oil available is Honda engine oil ..

Is honda oil compatible with Toyota cars ????