*0W20 or 5W20 scares me in the Theta II 2.4L GDI , I bumped up to 5W30 synthetic oil for the higher HTHS as well as to guard against fuel dilution of the GDI engine.
Hyundai / Kia 2.4L Theta II GDI Engine Best Oil Sweet Spot
- Thread starter ChrisD46
- Start date
A year later, and my outlook changed slightly. I now use 5W30 Synthetic year round with a OEM filter.
This is on both the Forte 2.4L and Sonata 2.4l DI. Sonata now has 67K miles, zero consumption, and engine pulls, and sounds just like new. The Forte is not DI, and also has no oil consumption per oil change interval, and sounds fantastic for the age and miles.
I change the oil every 5500-6200 miles, 2 to 3 times on the sonata per year, and twice on the kia per year. and again on Hyundai 2.4l engine OEM filters all the way. I used a m1 oil filter for 200 miles this past OC, and I was about to make appt a dealer for a engine check over haha. the valves sounded that bad on the forte. Changed out for OEM, and the valve tick went completely away.
I certainly would go to 5w30....probably a high-mileage version.
I know that in the 08' Elantra and 08' Sonata that I serviced both seemed to prefer 5w30 from an NVH prospective. (neither had consumption issues worth mentioning...maybe 1/3 of a quart if the OCI went beyond 5K.) The 2013 Kia Optima 2.4 was a different story....it used oil until I put 5w40 in the sump.
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0w20 up north is really nice to start the engine during the winter. With it, you don't even need a block heater!
I've been using Mann W811/80 filters in both cars last few years, they are same as OEM filters internally.
OP here : '17 Hyundai Sonata 2.4L GDI (non turbo) engine now has just shy of 50K miles . I've decided for this engine (like previous posters have said) a shorter OCI is more important than the oil used - as long as a 5W20 / 5W30 D1 - Gen 3 , SP rated oil . *I do believe this Theta II engine plays nicer with Valvoline Advanced / EP and Quaker State Full Synthetic / EP because of the increased moly content . Still , with mixed city / highway driving , by the time I hit 4,000 miles / 4 ~ 5 months the oil is black with soot and "fragrant" when I'm underneath observing a drain . (insert picture of me wearing WWI mustard gas mask here. 
) With what essentially is a severe service OCI - I believe this Theta II thrashes oil like it invented the term. Lastly , I believe I'm better off using a Fram Ultra XG#9688 oil filter versus the Hyundai OEM blue oil filter - the flow rate and filtering effeciency is noted to be a better oil filter than the Hyundai OEM oil filter plus I have zero start up noise , ticking or anything else oil filter related . Lastly for today , I want to try the new M1 Tripple Action 5W30 SP D1 - Gen 3 synthetic oil for one OCI just to see (great oil from threads here on BITOG). Still , the Valvoline Advanced / EP 5W30 and Quaker State Full Synthetic / EP 5W30 get high marks for at least being the quietest oils I have run in the Theta II 2.4 GDI engine to date and that is not likely to change.
) With what essentially is a severe service OCI - I believe this Theta II thrashes oil like it invented the term. Lastly , I believe I'm better off using a Fram Ultra XG#9688 oil filter versus the Hyundai OEM blue oil filter - the flow rate and filtering effeciency is noted to be a better oil filter than the Hyundai OEM oil filter plus I have zero start up noise , ticking or anything else oil filter related . Lastly for today , I want to try the new M1 Tripple Action 5W30 SP D1 - Gen 3 synthetic oil for one OCI just to see (great oil from threads here on BITOG). Still , the Valvoline Advanced / EP 5W30 and Quaker State Full Synthetic / EP 5W30 get high marks for at least being the quietest oils I have run in the Theta II 2.4 GDI engine to date and that is not likely to change.Using Ceratec in both cars, as well as daughter's '08 Acura. Plan is to not add more Ceratec or Moly for next 20k miles or so. It seems to be doing its job, actually.
