Hyundai/KIA Theta II multiple call campaigns

wemay

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Kendall, FL
I've always been fine using an x20 where recommended, but Hyundai/Kia have had a series of recalls/TSB on their (mine) Theta II engines in the past year that makes me thankful they have multiple viscosity recommendations in their manuals. From "machining debris" to "knock sensor update" which places car in limp mode at any hint of impending failure, these recalls make you sit up and take note. Although I've had great results from my 2.0T (147k miles) running mostly RC 5w30, and my 2.4s running mostly 5w20, these service campaigns have steered me away from the oil cap recommendation of 5w20 and RC 5w30 in any future oil changes. The 2.0T will strictly get an HTHS of 3.5 and the 2.4 will get 5/10w30. Thankfully, along with the recall, comes a hefty extended warranty on the engine to 120k miles, no questions asked.

Don't get me wrong, many will continue to use a 5w20 in these cars without complaint. It just won't be me anymore.

But i would have zero issue running 0w20 in vehicles where higher viscosity may not offer a needed cushion like current Mazda's or Toyota's.
 
They are having a boundary layer issue by bad design, in all of their motors it sure seems. Not all , but too many for comfort. My 2013 Elantra GT 1.8 was trash at 14,000. That one is not even on the bad engine list. Double secret warranty hiding, so they are not forced to recall that motor TOO. I have a 2018 Kona turbo and it is speced for 5-30 with the option to go to 5-40. I too am running a HTHS oil of 3.5. I bought the Kona since it checked every box for me, plus the 1.6T is on of their best motors, just by pure luck.
 
What is magic about 3.5 cP? You would get much better protection with a 15W-40 (~ 4.3 cP) if you think HTHSV is an issue, as you don't have to worry about cold starts in Florida.
 
Originally Posted by Gokhan
What is magic about 3.5 cP? You would get much better protection with a 15W-40 (~ 4.3 cP) if you think HTHSV is an issue, as you don't have to worry about cold starts in Florida.

Rather surprise you aren't recommending xW20 to OP ?
 
We welcome you to the thickies club
grin2.gif
 
Originally Posted by Gokhan
What is magic about 3.5 cP? You would get much better protection with a 15W-40 (~ 4.3 cP) if you think HTHSV is an issue, as you don't have to worry about cold starts in Florida.



I do in Minnesota......-20F Just a personal choice minimum to strive for a 5-30. Still looking for a 5-40 with very low calcium/sodium for summers here 90F. LSPI is an issue since, get a full 18psi boost at 1,750 rpm.
 
Most of the Hyundai/Kia engine failures (connecting rod bearings) are concentrated in MY 2011-2014 and, in 2015, a redesigned oil pump/balance shaft assembly was introduced. I use a 5W30 synthetic in my 2.4L and if I had a 2.0T I would be using a 5W40 synthetic. Engine protection trumps fuel economy in these engines.
 
I d used 5w-30 in all my Hyundai's since 2002. This includes the 2.7L,2.0L, 3.3L, and 1.8L. I have ran 5W-20 in them as well, but to be honest, they seem to "like" the 5W-30 better. I have never had any engine issues with any of mine, and have done 5K OCI on every one of them.
 
I think there are a lot of variables at play with the Hyundai/KIA engine failures.
(1) The machining process and proper cleaning of the block and all moving parts
(2) 11.1 compression ratio. That coupled with the use of 87 octane fuel. The knock sensors and ECM adjusts
the timing to compensate for octane levels. I recommend using premium fuel in all high compression engines.
(3) 0W20 or 5W20 oils are too thin and become thinner with fuel dilution.
(4) Improper maintenance. Not changing the oil & oil filter within the recommended period. Not changing the air filter
within the recommended period.

Thankfully, I haven't had any problems with mine and it's at 50,000 miles. 5W30 all the way.
 
Originally Posted by wemay


Don't get me wrong, many will continue to use a 5w20 in these cars without complaint. It just won't be me anymore.

.


We've had this conversation a few times over the years. I'm surprised you went back to 5w20. I've always said this is part of the issue, 5w20 is just to thin for these engines.
 
I got close to 100,000 miles out of a 1.6 in a '13 Rio running 5w20 without incident (gave it to my daughter and it was totaled). Have pretty well decided to go 5-30 from here out with 5K conventional OCI (really all semi-syn isn't it?) or 6K synthetic.
 
I hesitate to comment about what oil is best for the Gamma II vs. the Theta II, etc. but I've gone with the idea that a "thin" 5w-30 like PP is likely the best option for my Gamma II commuter....as is mid-grade gas. I'm probably more interested in issues with the timing chain than I am engine failures or ultimate longevity with the Gamma if I'm not going to have it more than 125K miles or so.

I'm not convinced that using a 3.5 HTHS oil in the Theta II will stave off engine issues if they're somehow baked in, but I don't doubt that the 5w-20 vs. 5w-30 argument would probably apply differently to these two engines.

My understanding is that the Gamma II has been a relatively trouble-free engine since its 2012 introduction. The Accent ( Gamma II engine ) apparently has the lowest recall / take-back rate ( .10 per 100,000 vehicles ) which is the least of any vehicle sold in the U.S. as of last year and the 5 year period since its introduction....so whenever I see these Theta-based threads I don't really gloat, I just laugh if they lump all Hyundai engines together and it's suddenly 1987 again.
 
Originally Posted by MuzzleFlash40
Originally Posted by wemay


Don't get me wrong, many will continue to use a 5w20 in these cars without complaint. It just won't be me anymore.

.


We've had this conversation a few times over the years. I'm surprised you went back to 5w20. I've always said this is part of the issue, 5w20 is just to thin for these engines.


Yes, we have. You can only bump your head on a wall so often. lol
 
One of the major issues with these 2.0L/2.4L engine failures in the early years at least, has been the oil pump/balance shaft assembly at the bottom of the motor. This unit has been redesigned and is in all the later MY engines and the long-block factory rebuilds (like mine). Kia has a forever warranty (unlimited miles/unlimited years - all owners) on these engines now. These later engines should do fine with good maintenance.

FYI: Mine ran very strong for 77K miles (I'm tuned with lots of bolt on mods) with excellent maintenance until the rod knock suddenly happened. My replacement was very fast and very well done. They even moved over all my bolt on mods at no charge or issue. I have NO complaints.
 
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There's a write up in Korean my iPad won't translate . Here's another showing 30 is legit.
http://www.hyundaisonatamanual.com/sonata296recommended_lubricants_and_capacities.html
I got it from the Hyundai forums where they say it's just another part of the long sad saga of the Theta 2 engine series,
The skinny from the Hyundai forum as a general consensus is this. keep it always synthetic oil, period. Then change that oil AT LEAST every 5000 miles . Then maybe...¬ it will be fine. As for filters that's a tough choice . Their OEM is a 25 micron filter, sort of mid range. A better one would be in order but here's the kicker. Hyundai way back in the dark ages of this mess with Theta2 put out a service bulletin mandating OEM filters. They were denying warranty claims for some based on just that. Then along came the law suit and recall spanking and they behaved themselves with a 100k / 10 year warranty extension on powertrain.
Now the Theta2 being direct injection is one dirty running mother and many say that 25 micron filter is too porous to catch much of the sooty spooge that the thing spits right back into the oil, flakes off the valve stems and gets ground up ect. So which do you use, good question. You're sorta screwed either way really.
Also recently Kia has been suffering from these same engines🤫. At least their extended is supposed to be 200,000 20 yr which is a heck of a lot more reasonable if you're a car keeper. I'll bet my pension that Kia will have the same rampant issues as time gots on.
When you look at the whole long term mess it becomes clear. They don't know what or simply cant fix this problem with sudden oil consumption , bearing spinning and debris plugging up the oil journals. If they had it would have happened long ago . After all it started in 2011, crawled into view in 13 when they said it had been remedied on 4/12 with that new block cleaning process in Alabama. The dead engines just kept coming ever after and even now continue to happen. So far they've budgeted $885 million to fix warranty dead engines. Today the secret weapon is a knock detector computer flash 🙌ðŸ½That keeps them paying for the tow as you drive your car in limp mode to the nearest dealer to get its new engine before it dies on traffic. That campaign just started so will surely expand in time. And as they say " The hits just keep on coming". They're catching on fire👌ðŸ¼
https://www.autoblog.com/2018/10/18/hyundai-kia-senators-engine-firws/?guccounter=1
The good news on this one though according to whispers is that it's the mechanics fault. Supposedly they're damaging something on the fuel system while installing that 🙄warranty new engine. Time will tell.....
Last but only the icing on the cake ( only for those of us blessed with one) hop on one of the online trade in calculators and punch in your ride💸💸💸💸💸. That trade in value drop faster than Stormy Danials G string. One guy on the forums said he took his Sonata in to one place for a trade and the dealer wouldnt even take it. 🤗
 
There have been so many threads like this that I can't remember how "rampant" these failure / engine replacements are for the Theta II. Does anybody have any data that says 3%, 8%, 51% of Theta II-equipped vehicles sold in X model year, etc.?? I used to be on a Hyundai forum and found that a lot of information was incorrect and supported hearsay more than empirical reality. Not being an apologist here but it would be nice to have actually numbers vs. descriptive terms. One in 20 would mean more to me than "these engines screw the pooch right and left" which would translate to be >50% to me..

I've never seen the Hyundai OEM filter referred to as being a 25 micron unit...more akin to 40-50 microns in the mid-90% range is the guesses I've seen as I think Hyundai still only references a vague nominal figure as the listed spec. Is there an official, tested spec at this point for these filters??
 
wemay, I had the exact same thought. Mine dilutes, and I don't know how much exactly. I used delvac because it ought handle soot better than PCMO, and the HTHS at 4.1 can drop to 3.5 after dilution and still provide ring protection. If I didn't have dilution, I would pick out an API 10w40 for that 3.5 HTHS, or A3/B4 30 weights, or HDEO 10w30 (also 3.5 HTHS).
 
One of the biggest reasons those engines fail is placement of cat converter right after exhaust mani and material in them that crumbles into ceramic dust and finds its way back into engine.

If one has access to those dead engines - cut the cat open and see what the filler is like ...

As far as oil goes, engines will be ok with lower viscosity like 5w-20 that they recommend but as long as you change synth oil every 4K miles or 3K miles for dino. That's if there are no metal shavings left behind as in some found in oil pans.
Also, cooling config is not good, coolant goes around 1st cyl, then 2nd and 3rd before it reaches 4th being already hot. Pistons' 2-4 walls suffer.
 
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