What Engine oil should be used in Suzuki cultus 2011

[chakraniazeez]

Kindly recommend me a good synthetic oil for (suzuki cultus 2011) which has good milage as well
Total Milage 107000

[engnr.mubashir]

10w 40
Shell
Caltex
Total are best of the best for local made cars.
I personally use 5w 40 fully synthetic from caltex and shell normally switch between them both lasts 10000 kms easily. Both gives me good average and protection as per me. Long ago I dumped zic oils because they were being consumed by my engine for no reason and and was giving poor mileage so then I switched to shell and caltex everything is butter smooth as per my experience. One thing I have also noticed that caltex has good amount of additives in order to clean engine.

[margallar]

i am happily using 10w30 caltex in both my margalla and cultus

[analyticsground]

I have cultus EFI 2011.
I had no idea what engine oil grade previous owner was using so I mistakenly poured 4 litre 10w-30 engine oil after which car started to produce gray and bluish smoke during cold start. I had reduced the oil level to 3.5 litres after noticing the mistake.
I drove around 1500 km and there was no oil or coolant level reduction.

Had to go for valve seals replacement due to smoke issue. Changed head gasket along with head facing. Mechanic suggested to use 20w-50 after valve seals replacement. There is no smoke now but I am not satisfied with 20w-50 as milage has dropped.
I am now planning to use 10w-30 or 10w-40.
Please advise which oil grade i should use after valve seals replacement as I don't want to use 20w-50.
Thanks

[Hassan1991]