Official should be 5w-30. Some authorized KIA service like NSS do use 5w-40 though.

You look at the label it says BHPetrol.. i dont remember KIA is using BHP oil.

Last service is obviously not done by SC since they used BHP sticker.
Many fake sifus out there believe older cars need to use thicker oil, hence the insistence on using 5W-40. This has some truth in it when you are talking about cars from the 80s, 90s or modern Toyotas that are still using those old engines. but not modern Korean cars like the Cerato. Another reason is due to price, 40 is usually cheaper than 30, so most workshop stock them and try to push it to owners.

Anyways, it doesn't really matter much as long as the engine oil is good quality, you can change it over to 5W-30 later.

No problem using 5W30, just drove my Cerato 2.0 2014 to Genting ytd. Current oil was Castrol Magnatec 5W30 which already done twice went KL<>Penang and Genting trip, no visible oil loss at all, great engine.

This post has been edited by voscar: Nov 27 2025, 10:48 AM

What brand does KIA SC use normally? As i read earlier Petronas is one of it.
Thanks

what do u think about low viscocity "high mileage oil"
i saw from western brand got put special additive formula

Total Quartz for engine Oil. Petronas nutella for ATF.

Follow manufacturer recommendation and change engine oil every 10k km if you are using good quality fully synthetic EO. Don't simply hantam and use those that claim all kinds of things especially those from the US.
If you are using local/Korean/Japanese car then it is quite straightforward, find the EO with the rating (SAE etc) that is suitable for your car and the viscosity that is suitable also.

If you are using continental cars, then follow the recommended rating, BMW, MB, PSA all have their own ratings, just use the suitable one. Viscosity different a bit does not really matter, as long as don't differ too much.
For performance cars, too thick oil can feel a bit heavy and affect performance slightly. Too thin might burn more EO, so need to top-up frequently.