Anyone does 7K-8K OCIs on conventional?

Car is a Chevy Spark. They only come with GMs latest small gas engines, which is a 1.4L NA, non DI, non turbocharged engine.
Synthethic is cheap in the states, here the cheapest "Full synthethic" (Per the bottle label) is at least $13 US or more + tax for the cheaper brands but i can get Chevron Supreme dirt cheap. Manual calls for DEXOS 0W-20 oil.
Usual commute is around 13 miles each way and every day or so i do some errands during the day which adds like 5 - 10 miles.
Not sure what spec the OLM is based on but as far as i can tell, it will reach 0% when i reach 7K to 8K miles.
All the miles are done in city driving, A LOT of stop and go, heavy traffic and prolonged idling.

I previously owned a sub compact city car from a Korean brand which you dont get in the states (Kia Picanto) and did the same OCIs but i drove the morning commute all highway which i wont be doing this time. After a couple years, the engine was running perfectly fine, engine looked fine from the oil fill port and i had no mechanical issues AFAIK but i knew that car was quite good mechanically since lots of people buy them and they are abused.
Given your circumstance, I would use the Chevron Supreme in 5W20 or 5W30 without any hesitation. It's good oil. I would change it at 5K miles or 8K kilometers since you're using it hard.
 
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TWO of my former employers had 2019 Kia Souls and would only do 8k changes on quick lube conventional oil changes. I warned them each that they are asking for an engine to grenade itself but both insisted it was fine, synthetic oil is a scam.
 
TWO of my former employers had 2019 Kia Souls and would only do 8k changes on quick lube conventional oil changes. I warned them each that they are asking for an engine to grenade itself but both insisted it was fine, synthetic oil is a scam.
KIA lists a half-dozen viscosities as suitable in these engines as well as API SM and even SL. No mention whatsoever of synthetic oil... Have their engines grenaded yet ?
 
Theory is nice but plenty of people will insist an analysis is vital but then refuse to accept that the oil could have been used 2x longer.
Truth be told we change our oil and especially the filters too often. "Cheap insurance" is "wasted insurance" too often.

No, I don't want to push oils to their outer limit to wring every last drop of life out of it, but as you said many oils are dumped with 50% life left in them. Also as you said, some demand to have a UOA but then won't extend intervals where its indicated they could and should.

All to their own though. They pay to play, not me.
 
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I used to in my 2009 Fusion, years ago when most of my mileage was highway.

It was the owner's manual intervals and every conventional I used met Ford spec.
 
In my Galant I used Supertech conventional and did approximately 4000-7000 mile oil changes. I had some varnish but no real sludge when I pulled the valve cover. Oddly using a synthetic may have caused a front main seal leak, that's what I get for overimproving things.

In my mom's Ford Five Hundred I used Motorcraft synthetic blend for 5000 mile intervals. We've put about 50K miles of that schedule on it, and presumably the dealer used bulk conventional for the 40K miles we had it prior to me doing oil changes.

I think if you're gonna do conventional do 5000 instead of 7000-8000, but an occasional 7000-8000 won't really hurt it.
 
The simple answer here is to follow the OLM and then do a UOA. Then make a decision based on data, not on personal preferences.

Easy peasy.

That’s what I did on my 3.7L Ford F-150. It was accurate, but surprisingly , there was almost no margin of error. 25-30% oil life remaining on the IOLM is about right if you want to be conservative but not anal.
But yes. We tend to argue with the UOA, don’t we?
 
Depend on how bad that Spark gets beat on the commute. Also helps to know what kind of weather is where you are (not sure on location) My biggest issue with be with idle and sitting time on that 1.4. It will handle that oil just fine, but since it sounds like it is pushing close to severe service- I’d stay 4-5k-especially if you are getting it “dirt cheap“......
 
In most other non-boosted, non-DI, older PFI engines, maybe. Wouldn't be real comfortable without putting that 7500 on very quickly though (think winter fuel dilution).

In an ECOTEC? Not in a million years. Many ECOTECs love stretching timing chains, and less than stellar oil is usually a contributor. I wouldn't even run high quality synthetics like Mobil 1 EP/AP, AMSOIL, or Redline for 7500 in an ECOTEC. My personal bias? I wouldn't use a 0W-20 either. 5W-30 or 0W-30 would be my preference. And I'm not against thin oils. I have 0W-20 AP in my 5W-20 spec'd Elantra right now. I'm just against thin in ECOTEC engines. As for the interval, 5K max, and that's if you don't short trip it in winter or run it low on oil. That's exactly the prescription I gave to one of my customers who owns a 2011 Terrain. Rotella Gas Truck 5W-30, 5K max, and a NAPA Gold. Even with that interval and his 90%+ highway miles, it still sounds like a sewing machine ready to rattle apart at 96,000 miles.
 
Almost, but not quite, I mostly do 10,000km (6200 miles) OCI, and sometimes this is on a conventional oil, but mostly a semi-synthetic.

However I use a heavy conventional such as GTX 15W40 which is rated API SN and Euro A3/B3. I believe 15W40 is a robust oil viscosity grade even for conventional oil, hence its common usage as a HDEO diesel truck viscosity grade.
 
OP, here ‘ya go. This guy did 11,500 km (7100 miles) on a Penrite (local Aussie brand) 15W40 convention oil. Toyota Yaris.

It did fine, only 5ppm iron wear, the viscosity is still in grade and ample retained TBN at 3.2

 
My first brand new vehicle, 95 2wd Tacoma with the 2.4l 2RZ-FE engine and I went 6k-7k OCI regularly for 10+ years and over 200k miles before I sold it for a 2nd Gen Tacoma. I used only PYB 5w30 and Fram OCD. My driving style was 90% highway though. Used oil always flowed with no abnormally black, thick, or strong smell so that was my routine. Prior to selling, I did a more thorough inspection of the cam and casting surfaces and they were yellowish hue varnishing and no sludge or caked up buildup.

Would I do it today? Probably not because for the last 15 years, it seems the price of synthetic is not that more expensive than conventional and sometimes even cheaper with promotions, sales, and rebates that just because of buying habits have forced myself to not using conventional anymore. Lastly, the mfg recommended oils for today's engines if you choose to follow don't offer this viscosity SAE grades.
 
I am in close contact with the service manager at our fleet maintenance yard. Most department vehicles are GM or Ford (tons of Tahoes and Explorers) and he says that they commonly use conventional oil for 7500-mile service intervals. He also said that most conventional oils nowadays are not truly conventional, there is always a certain amount of synthetic content. Finally he said they don't really see oil-related failures anymore, most mechanical failures are caused by improper use/abuse, some cooling system issues and transmission failures (probably abuse as well). The point is that 7500 miles may seem like a lot for conventional oil, but as long as the proper oil spec is being used and the prescribed service interval is being followed, you're good.
 
I would say it depends on your commute and driving habits (you already mentioned them)

I have 12 5qrt jugs of Chevron supreme 5W30 (6 are sn plus and just say Chevron supreme, the latest 6 I just bought are sp and say synthetic blend on them) and my commute in my 17 accord is 15.5 miles to work 99% highway. I’m going to start out with 5K mile interval and at some point do a uoa and see if I can go 6-7K miles on it, with a Fram ultra filter changed every 2nd-3rd oil change.
I have a uoa posted with super tech conventional 5w20 where I went 6300 miles , Blackstone said try for 8K miles, and the oil was changed at 50% on the OLM
 
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