I don't know. I'd have to dig it out and look.
Question about OCIs and conventional/synthetic oil
- Thread starter CZ75
- Start date
My interval is 5K although I do at least 2 oil changes before 1500 miles on a new car.
If I had certain Hyundai/Kia engines, It would be 3K. The design on the newest Hyundai Smartstream engines is questionable.
The ONLY reason I go to the dealer for oil changes is to have the oil change documented at the dealership system and CarFax during the warranty period for a newer car if there are free changes. After this, I will change the oil AGAIN myself at home for peace of mind. Sometimes I am too lazy to videotape my oil change, and my receipts aren’t useful since I usually buy my oil and filters in bulk quantities well ahead of time.
The warranty issue is touchy. Toyota is now pushing a ridiculous 0w-8 oil for its newest cars (HTHS of about 1.8 which will clearly lead to premature piston ring wear, only satisfying some Japanese spec made expressly for 0w-8) while the American manuals strongly push for 0w-8 or 0w-16 without expressly mentioning what oil will satisfy or void the warranty. I will only use 0w-20 or 5w-30 (or possibly Mobil1 0w-30) in my Toyota. So it’s easier to let the dealer document a change every 10K miles during the warranty period and then swap it out to something more protective at home.
If I had certain Hyundai/Kia engines, It would be 3K. The design on the newest Hyundai Smartstream engines is questionable.
The ONLY reason I go to the dealer for oil changes is to have the oil change documented at the dealership system and CarFax during the warranty period for a newer car if there are free changes. After this, I will change the oil AGAIN myself at home for peace of mind. Sometimes I am too lazy to videotape my oil change, and my receipts aren’t useful since I usually buy my oil and filters in bulk quantities well ahead of time.
The warranty issue is touchy. Toyota is now pushing a ridiculous 0w-8 oil for its newest cars (HTHS of about 1.8 which will clearly lead to premature piston ring wear, only satisfying some Japanese spec made expressly for 0w-8) while the American manuals strongly push for 0w-8 or 0w-16 without expressly mentioning what oil will satisfy or void the warranty. I will only use 0w-20 or 5w-30 (or possibly Mobil1 0w-30) in my Toyota. So it’s easier to let the dealer document a change every 10K miles during the warranty period and then swap it out to something more protective at home.
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It is odd Hyundai would make a questionable design like the Smartstream after the Theta II issues.
I'd double check to see what weight oil you can use without voiding the Toyota warranty. Those oil weights the manual pushes is light.
My owner's manual does say which may void the warranty. It is one that causes damage. There's really nothing touchy about it, apart from Internet amplifications and outright falsehoods that are often posted.
So much misunderstanding and misinformation on why the owner's manual grade recommendations exist and what is the reasoning for those recommendations.
Speaking of Toyotas, interesting that their manual does not specify a synthetic fluid. Gear oil for instance, just a GL-5, they do not call out a synthetic 75w90, just 75w90.....in my 09. I am using some Mobilube HD80w90 in mine now.
WS as another example is not a "full synthetic".
But to the OP question, my bet would be on more frequent changes, that meet a standard than the type of oil used.
I am at about 5 - 6K miles per year on my Ford a 2L with D.I.
I am doing Fall and Spring oil changes disregarding mileage (since it's short). That might work for you if Kia allows 6mo intervals. I don't know if you live in a cold winter climate. Surprisingly my engine ran the smoothest on a dealer Conventional (semi syn) and quite rackety on Mobil 1. The Mobil is showing good LTFE averages though, with good cold warmup run performance. Soon to really be put to the test with some -20 C. starts before a few days before Christmas!
There is no traditional, majority convention oil base if you blend to meet ILSAC/API SP spec. That is purely a marketing placement terminology, same with the term Fully Synthetic Oil.
There exist no higher tier "Fully Synthetic" ILSAC approval to my knowledge. though some product may be capable of extended service hours due to higher resistance to oxidation and other breakdown mechanisms.
ILSAC spec lubricants allow of typical OLM "extended" oil changes and is turbocharged engine approved regardless of basestock makeup.
- Arco
About seven years ago I had to remove that fluid from two vehicles that were dealer serviced (in North East U.S.) due to extremely poor performance after the lube service.
One was a Nissan Rogue the other a Subaru. The Subaru was giving indications of impending failure - rear differential howling on highway. The perceived problems luckily went away with a drain and fill with humble Supertech 75W90. The Nissan was evidencing cold drive issues in the DT (x-fer case and rear axle) likely due to excessively high viscosity.
- Arco
On the IH8MUB forum, many have used it will success. I recently changed the fluid, and it seems very smooth. It does not get that cold here in NC, so I am not too worried about it.
Maybe to "heavy" for the light duty applications? A LX570 is "light duty" of course, but it a pretty heavy SUV.....not sure that matters.
A local rock quarry tech I know actually told me about it, it is all they use. Of course it is not the same application.
I think I will run it for about 10k, and have it tested.
Ya never know, some service centers up here may have been sold BBLs of garbage gear oil. the two dealers were about 15 miles apart.
Ages ago at the garage we used Wolf's head, Pennzoil, Amalie bulk with no reported problems. I would use Pennzoil in my personal vehicles. Should never be having issues with light GL-5 gear oil in a T-case or 3rd member in non-severe service.
- Arco
Are your OCI a bit high for D.I. despite whatever the manufacturer recommends? It might be a good idea to have oil analysis done by a lab.
I live in the high desert. In the winter it gets cold at night but with low humidity.
Is oil described as "conventional" less than 50% natural, non-synthetic oil if it meets ILSAC/API SP spec?
There should be no dirt in the oil.
Propflux01
$100 Site Donor 2025
What exactly is questionable about the Smartstream design?
I was just commenting on what the other gentleman said about Smartstream. Look above. I guess I took what he said at face value.
Propflux01
$100 Site Donor 2025
I see. I was wondering because there have been few issues with it, despite its complexity, And I can say from experience it seems to run very well for what it designed for.
If you did a quick calculation in the old noggin, my OCI are typically under 2500 miles at 2x per year. I have done analysis early on when I had seen filthy fuel diluted oil. After break in this improved somewhat.
Many "synthetic" base stocks are crude petroleum derived - they undergo more refining steps than a group I or II. Recently there are basestocks available synthesized from natural gas by Shell operations (Pearl GTL) in Qatar, W. Asia/ME.
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That's the truth. You never know what you're going to get. I did the lube tech job for a while when I went back to college and I was probably the most anal person there....lube everything, pre fill oil filters (even cartridge ecotec filters because the timing chain wouldn't rattle on startup if I did it). But there were others that worked there that were not at all as fussy. One guy wouldn't do grease fittings. He would argue that it was just an oil change. No it's a "(LUBE), Oil and filter".
I haven't had anyone else do on oil change on my vehicles since once when I was 19 and it was middle of winter.
I didn't know synthetic oil had anything to do with crude petroleum oil or natural gas until recently. I thought it was completely different the way that say NutraSweet has nothing to do with sugar the way it is made.
The Marketing Dept. said they don't want you to know "unnecessary details"; proceed with caution.
