6 Months Since Last OCI

The ST FS oil in my current fill is rated for up to 10,000 miles, and they now have a higher tier oil that's rated for up to 20,000 miles. Geez, and my last OCI I had 1800 miles on the oil. I need to stop throwing away such good oil. At 6 months into this oil fill of ST FS, I now have 2,762 miles on it. So in 6 months I might have about 5500 miles on the oil, at 12 months in. That's where I should do my next OCI, not now. I think it's time that I finally break my 6 month OCI habit. This 10k oil can darn sure take me to 5500 miles over 12 months. There are people here who would run this oil for 24 months at 5500 miles a year.
When I got the car 1/8/2020 it had fresh Conoco Philips FS and I only ran it a few months before changing it to Castrol Edge, and then I drained the Edge at about 1800 miles and added ST FS. I did this because I was enjoying changing my oil and getting a feel for these oils. Now I need to run this good oil longer and get my money's worth for a change. 12 months / 5500 miles would make much more sense than some of my recent OCIs.
Most oil manufacturers that advertise 10,000 or 20,000 mile intervals also specify "or 1 year, whichever comes first".

I agree with your conclusion that 12 months / 5500 miles is the best course of action for your situation.

I once did a UOA on a 14 month / 3500 mile interval that also happened to capture the beginnings of a head gasket leak. Even with the elevated potassium and sodium and typical 3 mile trips 4 times a day, I still ended up with decent wear metals and a 1.9 TBN with Pennzoil HM 5W20 conventional oil. I'd bet good money that ST FS would do better under the same circumstances.
 
Anticipation, it's making me wait. I fully understand. Since telework and not doing 100 mile commute every day, I get ancy. I check my monitor every drive. Only have 2k miles on the last change and I feel I should be creeping up on the next. Nowhere near! 🤪
 
Most oil manufacturers that advertise 10,000 or 20,000 mile intervals also specify "or 1 year, whichever comes first".

I agree with your conclusion that 12 months / 5500 miles is the best course of action for your situation.

I once did a UOA on a 14 month / 3500 mile interval that also happened to capture the beginnings of a head gasket leak. Even with the elevated potassium and sodium and typical 3 mile trips 4 times a day, I still ended up with decent wear metals and a 1.9 TBN with Pennzoil HM 5W20 conventional oil. I'd bet good money that ST FS would do better under the same circumstances.
Yes, but that 1 year is geared more towards the short trippers.
My mother in law had the OLM trip on her Chevy Trax at 1 year, with only 600 miles driven, and 95% of that mileage was a 500 mile trip.
There is nothing wrong with that oil and it was not changed.

Just goes to show that every situation is different and there are many more things you can consider than just miles/time.
 
This is one of those threads where someone comes on and says, "Oil analysis is the only way to know what's going on."

My case?.....glad you asked.
Several oil analyses (cheap WIX ones from RA) say my 6K OCI is slightly wasteful so I'm bringing her "all the way" to the 7,500 recommended distance.
No fear here as this round had double the number of 700 mile highway jaunts.
Last OCI was 20 March @ 114,280 using either Mobil1 0W-40 Euro or Castrol 0W-30 Euro.
My biggest concern is "WIX Analysis Central" using the same methodology.
 
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Let me ask you something else:

Given that I do my next OCI in the Spring at around 5500 miles over 12 months, will my stash still be fresh enough?

My last 4 quarts of ST FS came from a 12 qt bag in a box I bought in May 2020 for $30.

My NAPA FS 0w20 is from three 5 qt jugs I bought at NAPA in April 2021 for about $13.40 each.
So if I run the ST, I will be running a NAPA OCI in Spring 2023, 2024, and 2025.
Will this oil be fresh enough then?
If not, I could take it back to NAPA and just buy fresh oil when the time comes for an OCI in future years.
 
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Let me ask you something else:

Given that I do my next OCI in the Spring at around 5500 miles over 12 months, will my stash still be fresh enough?

My last 4 quarts of ST FS came from a 12 qt bag in a box that I bought in May 2020.

My NAPA FS 0w20 is from three 5 qt jogs I bought at NAPA in April 2021.
So if I run the ST, I will be running a NAPA OCI in Spring 2023, 2024, and 2025.
Will this oil be fresh enough then?
If not, I could take it back to NAPA and just buy fresh oil when the time comes for an OCI in future years.
Just stop buying oil and change it yearly. The extra oil will sit just as well in your garage as it would in a warehouse.
 
Let me ask you something else:

Given that I do my next OCI in the Spring at around 5500 miles over 12 months, will my stash still be fresh enough?

My last 4 quarts of ST FS came from a 12 qt bag in a box that I bought in May 2020.

My NAPA FS 0w20 is from three 5 qt jogs I bought at NAPA in April 2021.
So if I run the ST, I will be running a NAPA OCI in Spring 2023, 2024, and 2025.
Will this oil be fresh enough then?
If not, I could take it back to NAPA and just buy fresh oil when the time comes for an OCI in future years.
I only buy enough for the next oil change, unless the discount is so steep it's nearly free. Oil will stay fresh if sealed, but who knows if that's what you still want to put in when the time comes? It's up to you whether you take it back and wait or hold onto it.
 
Let me ask you something else:

Given that I do my next OCI in the Spring at around 5500 miles over 12 months, will my stash still be fresh enough?

My last 4 quarts of ST FS came from a 12 qt bag in a box I bought in May 2020 for $30.

My NAPA FS 0w20 is from three 5 qt jugs I bought at NAPA in April 2021 for about $13.40 each.
So if I run the ST, I will be running a NAPA OCI in Spring 2023, 2024, and 2025.
Will this oil be fresh enough then?
If not, I could take it back to NAPA and just buy fresh oil when the time comes for an OCI in future years.
No such thing as "fresh" oil.
If the oil met the spec of your vehicle when you bought it, it will be good as long as it sits on the shelf till you use it.
I have (and many others here as well) have oil sitting on the shelf for years before use.
All the oil on my shelves is SN/SN+/SP, my vehicles need nothing newer than SM.
I need to check the date codes on my jugs, I am sure some of it is at least 5 years old now.
 
Glad to hear it. I searched this site for "old oil" last week and saw similar comments.
It's good that I'm finally starting to wrap my brain around the fact that I no longer need to change my oil and filter 2x a year. I'm now almost 7 months on my current fill and going strong.
In the Spring, I'll add some NAPA FS 0w20 and a Fram PH4967 and run it for a year. The following Spring I'll perhaps add the last 4 qts of my ST FS.
No need to worry about "getting fresh oil". I'm sure this stash will serve my Prius C well. It's been in my climate controlled closet since I bought it.
 
I changed my oil the other day with NAPA 0w20 FS.
I don't know if I'm going to run ST any more.
ST is probably very good oil, it's just that I seem to feel better using a name brand oil with NAPA by Valvoline.
As per how long I'll run the NAPA FS, time will tell.
If I can stand it I'll run it until next year at this time with somewhere between 5 and 6k miles but if I get that urge,
it's not going to break me to do my own bi annual OCIs.
 
I changed my oil the other day with NAPA 0w20 FS.
I don't know if I'm going to run ST any more.
ST is probably very good oil, it's just that I seem to feel better using a name brand oil with NAPA by Valvoline.
As per how long I'll run the NAPA FS, time will tell.
Supertech's virgin oil analysis (VOA) results look better than NAPA's. At least with 5w-30, ST has higher viscosity, higher TBN, and a better additive package. I have not seen any NAPA VOA for other grades, just 5w-30.

See this post for details:
 
I'm going to run NAPA oil for at least 6 months. Then I have 4 qts of ST and enough NAPA for 2 to 3 more OCIs.
But whatever oil I use, I'm sure someone here will tell me I should run _______ oil instead.

I got the NAPA on sale for $13.40 for each 5 qt jug and I'm sure it will be fine for 6 month OCIs.

I read something about ST having high NOACKs or something like that.
I can't sort out all this information.
I'll change my synthetic oil 2x a year with whatever oil I can get my hands on and I'd say my engine will be well loved and lubricated.

And then there will be people here who say I'm wasting oil by changing it at 3200 miles in 6 months, but rather than obsess over all the conflicting information about all these oils, I'd rather just keep on with 6 month OCIs and leave it at that. It might cost me $55 a year to do my own OCIs 2x a year but that's better than worrying about the possibility that 12 months would be too long for the type of oil I chose.
I did OCIs 2x a year for the last 15 years with conv oil in other cars. I just don't feel right about going over 6 months, because I can't confide in people here telling me the oil I chose wasn't the best oil I could have chosen for my application. I now have fresh NAPA oil in my engine which more than likely is better than 7 month old ST.
 
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I'm going to run NAPA oil for at least 6 months. Then I have 4 qts of ST and enough NAPA for 2 to 3 more OCIs.
But whatever oil I use, I'm sure someone here will tell me I should run _______ oil instead.

I got the NAPA on sale for $13.40 for each 5 qt jug and I'm sure it will be fine for 6 month OCIs.

I read something about ST having high NOACKs or something like that. I can't sort out all this information.
I'll change my oil 2x a year with whatever oil I can get a good price on and I'd say my engine will be well loved and lubricated.
🤣🤣
 
I'm going to run NAPA oil for at least 6 months. Then I have 4 qts of ST and enough NAPA for 2 to 3 more OCIs.
But whatever oil I use, I'm sure someone here will tell me I should run _______ oil instead.

I got the NAPA on sale for $13.40 for each 5 qt jug and I'm sure it will be fine for 6 month OCIs.

I read something about ST having high NOACKs or something like that.
I can't sort out all this information.
I'll change my synthetic oil 2x a year with whatever oil I can get my hands on and I'd say my engine will be well loved and lubricated.

And then there will be people here who say I'm wasting oil by changing it at 3200 miles in 6 months, but rather than obsess over all the conflicting information about all these oils, I'd rather just keep on with 6 month OCIs and leave it at that. It might cost me $55 a year to do my own OCIs 2x a year but that's better than worrying about the possibility that 12 months would be too long for the type of oil I chose.
I did OCIs 2x a year for the last 15 years with conv oil in other cars. I just don't feel right about going over 6 months, because I can't confide in people here telling me the oil I chose wasn't the best oil I could have chosen for my application. I now have fresh NAPA oil in my engine which more than likely is better than 7 month old ST.
I wasn't telling you what oil to run, just showing you that a virgin analysis of both oils in 5w-30 grade show that ST looks more stout than NAPA. 🍻
 
In 2 weeks it will be 6 months past my last OCI and I have just over 1700 miles on my NAPA FS oil.
I like NAPA by Valvoline FS 0w20 oil and should feel fine running it for a full 12 months.
It will be the first time I ran oil for 12 months.
It took a while for me to get out of the 2 OCIs a year mentality.
 
Rather than making a new post to rant about this once again, I thought I'd reply to this one again.

I went ahead and did another OCI in late April with PP 0w20. Then I said I'd try to run this oil for 12 months because IMHO PP is one of the better oils out there and it should easily go 12 months at only about 4k miles a year. But OCI time comes up again in 2 weeks and I'm feeling like doing an OCI again, PP or no PP oil. I'm even thinking of buying new oil and saving my other 16 qts of PP for later on.
I just feel like doing an OCI in 2 weeks to get that certain type of high that comes with having brand new oil and filter in your engine.
I'm thinking some ST or QS would be good for this one.
 
Rather than making a new post to rant about this once again, I thought I'd reply to this one again.

I went ahead and did another OCI in late April with PP 0w20. Then I said I'd try to run this oil for 12 months because IMHO PP is one of the better oils out there and it should easily go 12 months at only about 4k miles a year. But OCI time comes up again in 2 weeks and I'm feeling like doing an OCI again, PP or no PP oil. I'm even thinking of buying new oil and saving my other 16 qts of PP for later on.
I just feel like doing an OCI in 2 weeks to get that certain type of high that comes with having brand new oil and filter in your engine.
I'm thinking some ST or QS would be good for this one.
Mr Luke
I offer you a suggestion
(With all due respect)
Since you seem to have no problem wasting time and resources, how about doing a uoa every time you get the urge to change your oil.
Then kindly post your results!
 
From what I've learned over 30 years...reading,research,experience. 6 months or 3000 miles. Why?.because short tripping allows acids and fuel dilution too build up.that can,will eat the cams,inhibit proper lubricatio. and sheerng of oil. 5w30 oils very often after 1,700 miles start steering down between 5w20 and 5w30.
When I got my liscense,1992. My dad gave me his beater car1983 Buick century. He bought a used Saturn from dealer, low miles.1991 model. Every 6 months,we averaged about 1,700 too 2,200 miles. Oil changes on both. That was oil not as advanced as todays. He used our local Mobil gas station.
I do know,the mechanic used dealer only filters(sent driver out too dealer too get filter),but dunno what oil he used. Mobil one I think.pretty sure it was synthetic he used.
Change oil 6 months,guarantees your flushing out any potential water,acids,fuel.carbon...
 
Probably no issues with your plan but w short trips I would do every 6 months. Here is why I am in favor of it: I have 3 vehicles for the 2 of us. One is my truck and the other is our Expedition, Expedition is mainly for towing our camper, neither should hit 5k in a year. The wife's Honda is a 20mile one way commuter M-F and gets 5k oci. The others not so much as my commute was 8miles one way but now I will be walking most of the time once I go back to work. She will probably take my truck and the Expedition 1 or 2 a month to run them as well. My plan is every 6 months oci for the 2 bc it gets someone under the hood and vehicle to put eyes on stuff. They both will be getting QSFS or PP even though they won't need it for piece of mind and preventative measures. As at one oil change just after we got the Expedition last year I found a coolant leak at the manifold gasket. Just a thought but probably nothing wrong w once a yr you plan on if you take it out for long drives a couple times a month. Good luck.
 
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