So let me start another thread on this. It's now 2017. Newer cars have oil life monitors. Yet I see late model cars in the UOA section with 5000 mile or less OCIs, with great results and lots of life left on the oil. Why? I mean it's better than 3000 mile OCI's, since we're not in the 70's anymore, but 7500 mi OCIs have been the norm for Japanese designs for over 15 years now.
Dead Horse Warning: What's with the short OCI's?
- Thread starter homeyclaus
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Severe service?
Those that find it necessary to perform a UOA on a late model car are likely change their oil prematurely. Which is what you're seeing.
Direct Injection
Direct Injection Turbo
may cause...
Fuel Dilution (shearing)
Rapid oil breakdown
Originally Posted By: wemay
Direct Injection
Direct Injection Turbo
may cause...
Fuel Dilution (shearing)
Rapid oil breakdown
My rogue OM says 6 Mo or 6 K mi or risk no warranty if engine lunches and oil is toast.
Oh, wait! Nissan doesn't want myservice mgr to make a warraty claim so - forget what I just said.
I can only speak for myself. When I see fuel dilution and viscosity out of grade, I will happily change my oil.
We've been brainwashed with scare tactics by oil companies for generations!
The biggest risk to late model engines is not the oil OCI, but owners who don't lift the hood and check the oil level
and run engines till the oil light comes on with 1 qt in the pan then complain their engine is blown! Jeez!
Any of the thousands of tests show you have to run way over a long OCI to get to a TBN of 1.0 or less!
I know if I go on a all day 500 mile hiway run 60 MPH or more, I'll bring some oil to top up, I'll be about a 1/2 qrt low!
My 2014 Subaru specified 7500 OCIs for non-severe service, but the next model year (2015) it was changed to 6000 miles without any obvious changes having been made to the engine. This may have been a blanket change due to ongoing oil consumption problems with other Subaru engines, but I also wondered if the DITs were just chewing up oil faster than expected. No OLM in my vehicle, either.
I stick with 5000 mile OCIs because it's easy to remember and I like having just a bit more margin.
The "oil" can go 10K miles, but it gets full of crud. That's why people change it out. My 2012 Equinox 2.4 gets the oil changed every 2000 miles or 3 months. The really black, doesn't look or smell like oil stuff that comes out needs changed. I don't need to see a UOA to tell me what I hear, see and smell. At close to the 2K/3 mo the VVT valve train starts to get noticeably louder. This car sees 15 to 30 starts a day, at least. It's Direct Injection. GM backed the OCI up because of timing chain failures, because of dirty diluted oil. That's my reasoning for "this" car.....and a good friend tech who works at a local Chevy dealership agrees. 
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They're trying to avoid the formation of varnish.
Nobody wants stir-fry pan stains on the inside of their engine.
If you own one, I wouldn't recommend blind 10K mile OCIs with a GDI or TGDI as they may require a little more vigilance. I can see 5K mile OCIs as standard for these engines so "short OCIs" is a relative term and not an absolute one. It's definitely a dead horse response if someone just thinks of the oil and not the application when they recommend long OCIs.
you guys who love to abide by the olm go ahead and do that in my 17' civic 1.5t. then run a uoa and tell me what you get.
Oil is cheap if you shop right.
I don't understand the sort of duration test most want to run on your own vehicle at your own expense. It's simple to change the oil and cheap. 5,000 miles is my limit although I change it more at 2 or 3 k in 6 month intervals because I don't drive my vehicles much.
Other things to keep in mind are:
-Most dealerships make more money servicing and repairing vehicles than they do vehicle sales
-The manufacturer does not care how long your vehicle lasts outside of warranty
-10,000 miles on a good synthetic is much different than 10,000 miles on the cheapest quickie lube conventional
-10,000 miles of easy highway driving is different than 10,000 miles of short trip driving
From reading here and what I've noticed is it's all application specific.
My Matrix, I'd like to go 7,500-10,000 mile OCI's on a good synthetic, however it calls for a 5w20 or 0w20, and I'm not sold on a good synthetic being robust enough to protect in Florida heat at an Xw20 weight. I am awaiting an analysis of Castrol Edge HM 5w20 with 6,200 miles to see how that oil looks. Those results will affect my future judgement. Current OCI is Mobil1 EP 5w20.
My G20, I am fully confident I can do 5,000 with Pennzoil Platinum Euro 0w40. Probably could go 7,500. But for now I am okay with changing it out ahead of time because the cost isn't very high and still exceeds my original thinking of 3,000 mile OCI or the engine explodes 
The Jeep however, gets changed every six months or 3,000 miles due to the mileage; 282K and going. I will probably stick with Valvoline Maxlife 10w40 though. The HDEO 15w40 seems a bit thick and I diluted it with some Pennzoil 0w20 I had on hand.
SO! All my reading and (limited) experience leads me to think 3-10K OCI's vary wildly.
Big reason as to why there is no "Best oil"
The Jeep however, gets changed every six months or 3,000 miles due to the mileage; 282K and going. I will probably stick with Valvoline Maxlife 10w40 though. The HDEO 15w40 seems a bit thick and I diluted it with some Pennzoil 0w20 I had on hand.
SO! All my reading and (limited) experience leads me to think 3-10K OCI's vary wildly.
Big reason as to why there is no "Best oil"Originally Posted By: homeyclaus
So let me start another thread on this. It's now 2017. Newer cars have oil life monitors. Yet I see late model cars in the UOA section with 5000 mile or less OCIs, with great results and lots of life left on the oil. Why? I mean it's better than 3000 mile OCI's, since we're not in the 70's anymore, but 7500 mi OCIs have been the norm for Japanese designs for over 15 years now.
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