What is your standard OCI interval?

5k on my 2011 GMC Terrrain. After sending a few oil samples off to blackstone I have found that 5k is around the time the gas in the oil starts to thin the viscosity down to a 5w-20.
 
6k in the Genesis (per the owner’s manual), also the Sonata. 4-5 months.

3k-5k in the Jeep. This one takes about 18 months usually.
 
I do 3k OCIs. Been doing 3k religiously since 1970..
Group I conventional oil can turn to sludge/varnish at 3k miles due to it's inability to handle higher engine temperatures.
But any group III synthetic should be able to make it to 5k miles without incident.
 
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5000 to 6000 miles once a year with
Castrol Magnatec 5W-20 E with the 948b spec and OEM Ford oil filter (Mann filter) on my
2018 Ford Focus St-line 1.0 EcoBoost 125hp,
oil capacity 4.7 qt with filter.
 
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I don't like wasting money on anything but since this is an oil site and an oil discussion I will keep my comments related to that. I just wonder how anyone who is a long term member of this site can still do 3k oil changes? I did 3k oil changes before I found this site, but since then I have realized how much time and money I was wasting. And I haven't had a single issue with any of my engines, even though my OCIs have been between 6k to 10k on all of my vehicles for 22 years now. There are very few situations that would call for a 3k OCI these days. Even if I was being ultra conservative I'd never do it sooner than 5 or 6k. My UOAs over the years have proven that I haven't been pushing my oil too far at all.
Glad to hear that you've had some good results with longer oil change intervals.

One thing to keep in mind is: UOA's don't measure sludge/varnish accumulation caused by extended oil changes.
 
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Glad to hear that you've had some good results with longer oil change intervals.

One thing to keep in mind is: UOA's don't measure sludge/varnish accumulation caused by extended oil changes.
They can give you a good idea though, if you don’t push the oxidation levels too high for instance. And the fact that my engines never saw any degradation in fuel economy points to them not being sludged up. It’s not as if I was using poor quality oils and running 25,000 mile intervals. I have always used good quality synthetic oils that could easily achieve the intervals I was running. It’s not like my 6-10k intervals were all that extended anyway. Definitely not intervals where sludge would be a concern.
 
I used to do 8-10-12k miles, especially if highway miles.

Now, everything- 5k miles, no matter. I don’t have a vehicle that sits for long periods, so 5k.

Every vehicle I own I plan on keeping it forever.
 
I don't participate in: "I change my oil more often than you", because, I have more time and money to waste. I just follow the manufactures recommendation and I did validate the results with a UOA at ~25,000 miles on a 5K mile run. Without a UOA everything else is just an opinion and Like Judge Judy statement, My opinion is the only one that counts. -) Ed
 
Would anyone be doing 10k OCI with SuperTech Full Synthetic oil for years.
Was just wondering if it can handle 10k OCI without issue.

Also is anyone using SuperTech Full Synthetic in Ford Ecoboost engines (which are known for being hard on the oil)
and what OCI are you doing?
 
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Depends on the vehicle. Simple port injected engines I do 5K city driving / short trips, and 7.5K or greater if mostly freeway. I've done plenty of 10K+ runs on my '96 Maxima with no ill effects and good UOAs.

On my more modern DI engines, I stick to 5K across the board. Our Kia van is 100% mixed driving, a mixture of short trips, short distance, highway, etc. I'm okay with 5K, but visually (and confirmed with UOA) it could probably go more. My T-GDI Buick, I do 5K also despite being mostly highway. Its oil gets very dark (compared to my other engines) after 5K, and despite UOA being impressive, it always shears down a grade.
 
Would anyone be doing 10k OCI with SuperTech Full Synthetic oil for years.
Was just wondering if it can handle 10k OCI without issue.

Also is anyone using SuperTech Full Synthetic in Ford Ecoboost engines (which are known for being hard on the oil)
and what OCI are you doing?
I been running 5w30 Supertech regular full synthetic in our 2016 Fusion 2.0 ecoboost for most of it's life usually 6 month intervals (4,000 to 5,000 miles) car has 80,000 miles. I think it's a good oil for my intervals. I'm sure I go longer, but I get bored.
 
I been running 5w30 Supertech regular full synthetic in our 2016 Fusion 2.0 ecoboost for most of it's life usually 6 month intervals (4,000 to 5,000 miles) car has 80,000 miles. I think it's a good oil for my intervals. I'm sure I go longer, but I get bored.
Thanks for that info. It would be interesting to find someone whose done 10K mile OCI with SuperTech Full Synthetic 5W-30 in their Ford Ecoboost engine since new, and get their feedback as well.

I've always been doing a 4k mile / 6 month OCI with full synthetic 5W-30.

I think one thing that is convincing me that 5k/6 month OCI is ok is the recent move by Pennzoil to market their Full Synthetic oils as 15,000 mile oils by saying it right on the container. Pennzoil has always been very conservative on OCI, but now even they are going to the 15k OCI recommendation. I know there is a lot of exclusions in their fine print, but still, it's convinced me that 5k mile / 6 month OCI's are fine for any engine out there, if SuperTech markets their full synthetic oils as 10k mile OCI, and Pennzoil 15k mile OCI.
 
745Le XDrive. Between 8-10k with BMW Dealer Service has per 20k schedule

Audi Q2 Every 7/8k with 15k interval at Audi Dealer.

Basically works out as an Annual service really.

Smart For Four Whenever I remember, was 6 monthly regardless till Covid, with one Service being done at a Mercedes/Smart specialist.

Since Covid I just do it when I remember, so around 8/9k it is a 2017 with 64k miles.

I have done an oil and filter at half the Manufacturer Interval and done Main Dealer Maintenance or Specialist Garage at the Factory Interval for years now.

Works for me as in the UK lack of proper documented history devalues a car when you trade it in to a Dealership.
 
Around 5,000 with 5w-20 / 5w-30 synthetic oil for the '18 Accent and 0w-20 synthetic for 8,000 or so miles for the '13 Fit .
 
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