2025 Kia K4
- Thread starter JeepJKU85
- Start date
It's a mixed bag on this forum.
Some people freak out at the idea of using an oil outside the manufacturer's specs while the car is under warranty. I've asked many times, and NOBODY has ever provided evidence, of a manufacturer declining a warranty claim, or even asking for evidence, of what oil was installed into a user serviced vehicle. Yet, we get countless posts stating..."while under warranty I'm running the spec oil"... Truth be known, engines don't fail under warranty, so the concern is unfounded, but that doesn't matter, there are still many that hang tight to the belief that you MUST use the OEM's spec oil, otherwise their warranty will be void.
On the other hand, there is a large contingent that feels that you must run a thick oil to protect the engine. Any oil thinner than 30 is the elixir of the devil in the eyes of these people.
Which side of the fence are you on? Ha ha. Personally, for my Civic, which calls for 0W-20, I've run various oils, including the stock spec and 5w30, and the engine doesn't care. Unless you have a special use case, suggesting reason to deviate, I'd just use the 0w-20. If you have a use case suggesting something thicker, run that. Honestly, it doesn't really matter much. Exception being, maybe, running high mileage between changes. My opinion, for a normal car, run SuperTech or Costco oil, OEM spec, and change it at 5000 mile intervals. The engine will likely outlast the rest of the car that way.
Some people freak out at the idea of using an oil outside the manufacturer's specs while the car is under warranty. I've asked many times, and NOBODY has ever provided evidence, of a manufacturer declining a warranty claim, or even asking for evidence, of what oil was installed into a user serviced vehicle. Yet, we get countless posts stating..."while under warranty I'm running the spec oil"... Truth be known, engines don't fail under warranty, so the concern is unfounded, but that doesn't matter, there are still many that hang tight to the belief that you MUST use the OEM's spec oil, otherwise their warranty will be void.
On the other hand, there is a large contingent that feels that you must run a thick oil to protect the engine. Any oil thinner than 30 is the elixir of the devil in the eyes of these people.
Which side of the fence are you on? Ha ha. Personally, for my Civic, which calls for 0W-20, I've run various oils, including the stock spec and 5w30, and the engine doesn't care. Unless you have a special use case, suggesting reason to deviate, I'd just use the 0w-20. If you have a use case suggesting something thicker, run that. Honestly, it doesn't really matter much. Exception being, maybe, running high mileage between changes. My opinion, for a normal car, run SuperTech or Costco oil, OEM spec, and change it at 5000 mile intervals. The engine will likely outlast the rest of the car that way.
My opinion, 5w30 from day one. I myself was willing to gamble with my car as Hyundai/Kia was pushing 0/5W-40 on their turbo cars in 2015 to 2017ish, because they were blowing up engines. Plus, they are "world cars" so I was going by what EVERYONE in the world "could run" but North America as it was ONLY CAFE standards for "mileage". If I bought another one at 500 miles the 0/5W-20 would be the last of that viscosity that the car/truck would every see as long as I owned it. Don't push long oil change intervals. You own a Hyundai/Kia one of the worst cars/trucks to push oil on. Technically owning a Hyundai/Kia dictates categorizing your car/truck "rough service". Valvoline Restore and Protect will be your friend in the future. A high percentage of them "coke up" their piston rings. No everyone though, those are the outliers (the not everyone) . Just my opinion. Take it or leave it.
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Does the owner's manual allow 5w30 under any conditions? My 2024 Forte 1.6T calls for 5w30, I assume because of the turbocharger. I can tell you with all certainty that 5w30 is not going to have a detrimental effect on your engine, with the exception of .0001 MPG loss. However, if you experience an engine problem that involves an internally lubricated part and they ask for your oil change records, you could be facing problems using oil that isn't specified. You're dealing with a manufacturer that's had to spring for many, many engine replacements over the last decade or more, they're going to get out of replacing yours using any method available to them.
My advice would be to consult your owner's manual, use the thickest viscosity it allows, and use a quality, reputable oil.
My advice would be to consult your owner's manual, use the thickest viscosity it allows, and use a quality, reputable oil.
I'll probably go 5w30 HPS RP for the stout add pack. It's done exceptionally well on my 3.6 Gladiator. Luckily this 2.0 version is fuel injection and not GDI nor turbo praise the lord 
. Book says 6k for severe I believe but I will go 3 to 4k at max just because oil is cheap motors aren't.
. Book says 6k for severe I believe but I will go 3 to 4k at max just because oil is cheap motors aren't.Thanks.Congratulations
Hyundai/Kia manuals have had ambiguous language for years regarding oil choice. Lately they only list one viscosity (0w-20 in your case), but right after that it says that a higher viscosity is ‘required’ in hot weather. But then proceeds to say to only choose the recommended viscosity, or something like that. FWIW, the engine in our Carnival only lists 0w-20, but in the Middle East it can use 5w30. Don’t know how a Floridian or Arizonan summer is different from the temps in the Middle East 
I personally have decided to use a 30 grade in the warmer months at least in our Carnival. Our vehicle gets the oil really hot in normal driving. Add in a little fuel dilution here and there, and the 20 grade would be so thin at 240F oil temps.
I personally have decided to use a 30 grade in the warmer months at least in our Carnival. Our vehicle gets the oil really hot in normal driving. Add in a little fuel dilution here and there, and the 20 grade would be so thin at 240F oil temps.
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What oil weights does the OM allow for ? In a Kia engine I would use the thickest oil weight allowed by the OM . My Hyundai engine allows for 5W20 , 5W30 & 10W30 in the OM - I’ve opted for 5W30 the majority of its life. My wife’s Kia 2.0 L (PFI) Seltos also gets 5W30 with no issues running it . In a new engine I would try Pennzoil Ultra Platium 5w30 , Mobil 1 Extended Performance 5w30 , Mobil 1 5W30 Truck & SUV or Mobil 1 ESP 0w30 (best oils at Walmart with best prices) . Keep OCI’s at 4K to 5K miles with a Hyundai / Kia engine and you will be doing your part to prolong engine life .
Propflux01
$100 Site Donor 2026
0w-30 Mobil ESP.
Hyundai/Kia manuals have had ambiguous language for years regarding oil choice. Lately they only list one viscosity (0w-20 in your case), but right after that it says that a higher viscosity is ‘required’ in hot weather. But then proceeds to say to only choose the recommended viscosity, or something like that. FWIW, the engine in our Carnival only lists 0w-20, but in the Middle East it can use 5w30. Don’t know how a Floridian or Arizonan summer is different from the temps in the Middle East
I personally have decided to use a 30 grade in the warmer months at least in our Carnival. Our vehicle gets the oil really hot in normal driving. Add in a little fuel dilution here and there, and the 20 grade would be so thin at 240F oil temps.
We picked up our ‘26 Carnival on Saturday. As you mentioned, 0w-20 is the only oil viscosity listed in the OM. “Normal” OCI listed as 8k, “Severe” listed as 5k, which is what I will be going with.
Gonna run the FF for a while yet but will be switching to 0w30 for its first change.
Kia / Hyundai...5w30. If it was my K4, Mobil 0W-40. If really cold where you are, go 0W-30.
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Is this 2.0 a multi port non turbo?
wemay
Site Donor 2023
Congrats on a nice ride. Wishing you many years of safe, reliable and enjoyable motoring.
Concerning the oil? Either/or will do. Not a significant difference between ILSAC 0w20 and 5w30 unless you're below freezing.
Concerning the oil? Either/or will do. Not a significant difference between ILSAC 0w20 and 5w30 unless you're below freezing.
Correct. Was so happy to find a fuel injection non turbo. If a motor needs a turbo it wasn't built correctly.
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0W20 is all that engine needs. Not necessarily true turbos could be used for several reasons in an auto makers design.
I agree but its for smaller displacement and to make more power at the costs of long-term reliability. Turbos are junk and always will be. No replacement for displacement no matter how much manufacturers try to put a 100 pounds of **** in a ten pound bag.
Well, your opinion is backed up by the real-world experience of thousands of Hyundai and Kia vehicle owners.
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