This is from WagonRs owners manual from 2018.
Suzuki Pakistan recommends 0W20.
But for sasta and tikao 10W30 is an ideal oil. I have had been using 0W20 till 70,000 kms. No issues but since my car does 5000 in under 2 months. I have switched to 10W30 just to save money.
I am getting similar fuel average figures. Does 5000 kms nicely. No oil reduction as such.
PS : If previously you have been using a thicker oil grade, its not recommended to shift to thinner oils.