Hyundai Theta (G4KC) 2.4L

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May 4, 2007
What is everyone running in their 4 cylinder Sonata or Optima? My 2010 Optima's owner manual allows for 5w20 through 10w30. However, the oil fill cap says 5w20. My current fill is M1 5w20 for the winter time and I plan on running it between 5K and 7.5K and then sending a sample off to the Stoners. M1 was not my first choice and I actually wanted some QSUD but the M1 was free. I am basing my oil choice on price only for this engine. It seems to run good on just about anything. My trips are generally VERY short with a 2.2 mile trip to work and then back each day. It does see some cross town trips and highway trips to keep the oil moisture free. I am running 5w20 because of my short trips and winter temperatures. However, I think come spring I will flip a coin to see if I will run MC 5w20 or some QSUD 5w30. The MC 5w20 is up in price enough that the QSUD is a nice upgrade for essentially nothing ($18 vs $19).
Those engines are pretty solid and you can't seem to really make a bad choice. Personally, I'd run Mobil 1 0W-20 AFE for most of the year, and maybe 0W-30 AFE in summer. They used to allow for everything multiweight up to 15W-40...
As long as you are driving at highway speeds for 20 miles or more every once in a while then you are fine with any oil. This was the last year for the non gas direct injection engines that automakers are experimenting with on the public. I would hate to see a short trip UOA on a GDI engine.
The Mu series 2.7L V6 in my 2008 Santa Fe was the same way. It recommended 5w20 & had that stamped on the oil cap. However the manual showed a crazy allowable range, like 5w20 through 20w50 depending on your conditions. I always ran synthetic 5w20 @ 7Kmi OCIs, but I drive no less than 1500mi/month. Joel
I do 5w20 all year long in my Sonata motor and its always been good. I would do a 0w20 if I ran synthetic though but I would rather do DINO oil.
I've been running valvoline or VYB lately at 5k OCI, but I am thinking of going to TropArtic as I can get it cheap at Sam's Club. TA seems to be very similar to Motorcraft. I always use a Napa Gold or PureOne filter.
i have an 06 tucson withthe 2.0 engine at first it used to get 5w-30 syntec with some cheap filter and ran a bit loud. latet on in its life i changed to 5w-30 ultra with oem filter and the engine is super quiet at idle now i have the first fill of 5w-20 ultra and cannot tell the difference. but u should definitely use the oem filter there is a tsb out for it plus its a very solid filter.
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