Dr Saheb
Welcome to club. Always make your following habit specially in Karachi:
1. Buy Suzuki API SG 10W-40 only from Suzuki3S dealers
2. Always change Air filter and oil filter with every oil change
3. Change Engine oil, + Oil filter + Air filter after every 5,000 Km
4. Change your gear oil after every 30,000 Km
5. Check your radiator coolant level and conditon