Brother,
Good to know about your new altis. Its good car.
Well I suggest as follows
For first 40K use fully Synthetic oils with viscosities as 0-20 or 5-30 or 0-40 (Exceptional case).
From 40K to 80K, Semi Syenthetics. Viscosities like 10-30.
From 80K to 130K, Semi Synthetics. Viscosities like 5/40 would be the best.
From 130K to 160K, Partially Synthetics. Viscosities like 15/40 would be the best.
From 160K onwards, use 20/50.
But instead of believing local companies (Caltex, Total, Shell, PSO, Toyota, Suzuki, etc.) plz choose good companies. And according to the availability in Pak. presently I feel PTT Performa is good company. Oil is being manufactured in Thailand and directly coming. Not being re-packed here.
SINOPEC is Chinese company but manufacturing oil in Singapore. Its not good.
Kixx, just ignore.
Liqui Moly & Mobil1 are the best, but cannot find the 100% Original here.
Cheers & LOVE.