My car is Suzuki alto japan 2017. According to the owner's manual, car manufacturer recommends 0w-20 or 5W-30 engine oil. But the previous owner has used 10w-30 oil. The average temperature of the area I live in is 27°C. Temperature ranges from 25 to 32°C (77 to 90°F). Does it matter if I use 10W or 5W?
I have read that less viscous oil tend to break under high temperatures. But a mechanic advised me to use 0w-20 since the engine is small and have very small clearance in engine parts.
Which oil is better for the engine life 0w-20 or 10/5w-30?