What oil do Americans actual need for 3k OCI's?

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As an old oil formulator, I'm constantly amazed by posts from the US which say 'I change my oil every 3,000 miles' or 'I don't want black oil in my engine so I change it when it starts to go dark'. It makes a complete mockery of everything that the motor lubricant industry has done over the last few decades. Better base oils, higher treats of increasingly expensive additives, eye-wateringly expensive oil development and Byzantine qualification processes based on an ever expanding suite of engine and rig tests...it all counts for nothing when you routinely dump your oil at 3,000 miles!

And you can see the evidence for this as plain as daylight in BITOG's UOA section. There's virtually no evidence of oil viscosity change either upwards (because of oxidation) or downward (because of shear) and both wear metals and additive depetion are laughably low compared to what a professional formulator would consider acceptable.

Well today, you'll be pleased to know 'I come to praise Caesar, not to bury him'. Reluctant as I am to say it, the US way of doing things does appear to work. One thing I see a lot of on BITOG are posts from people who have cars that have done 400,000+ miles and are still going strong. In fact I'm surprised you have so many old bangers (beaters) in the US because my last three cars were more or less knackered after ten years and 120k miles!

So I posed myself the question, if Americans are going to continue changing their oil ever 3k, should anything change? I came up with two answers...

If your car is new and under warranty, then just do what the OEM recommends. I don't always agree with what OEMs recommend as so much of it self-serving twaddle but if it preserves the warranty, swallow the excess cost and just do it.

However, if your car is older and out of warranty, then I would say there's case to be made for using a significantly cheaper oil that doesn't necessarily comply with GF-5 (or GF-6 if it ever surfaces). My thoughts are...

- most engine oils in the US are now made from cheap but high quality Group II base oil. These are way more resistant to oxidation than Group I's. Properly treated with additive, the chances of these oils oxidising to the point where they start precipitating sludge within 3k miles are almost nil. I doubt if many would even darken that much. Additives should focus on keeping the oil stable over 3k miles. 1% of light ZDDP (equates to about 950 ppm of Phos in oil) plus 2% 400 TBN over-based detergent (equates to about 8 TBN in oil) would probably do the trick.

- if the above is valid, then there's a good case to make that the oil doesn't need to contain any ashless dispersant. Sludge only needs dispersing when it's being formed which is the point where oxidation rockets out if control. That point would not be reached in 3k miles so it should be safe to remove it.

- if this occurs a couple of things happen. For any given viscosity grade, the NOACK volatility of the oil decreases significantly which I'd argue is always a good thing for any engine. The second thing is you knock out a least a half (and possibly more) of the expensive additive that normally goes into oil. Given that additive typically costs four times as much as base oil, the overall affect on the price of the finished oil would be significant.

- the final thing I'd say is that if the lubricant industry has proved anything over the last decade, it's that normal engines don't need overly thick, or overly thin oils. Your cams, bores, rings and bearings won't wear away to nothing in 3k miles if you run a 20 weight oil containing 1% ZDDP. Likewise, unless you live somewhere that's life-threateningly cold, you probably don't need a 0W oil. Even the case for having a 5W is marginal for great swathes of the US. Indeed, 20 years ago, most of the US ran with 10W30 oil and life went on as normal. The only reason why 0W & 5W are pushed so hard today is because OEMs can claim CAFE credits regardless of how much this adds to the cost of the oil you pay for. And it's not like the average American is actually interested in fuel economy is it?

- this being so, maybe over 3k miles, a lowly 10W20 oil containg 3% DI and no VII polymer might suffice. And that would be so, so cheap to make...


I suspect this speculation will never amount to much but in the event that Mr Stumpy Fingers ever gets his hands on the levers of powers and trashes the entire US economy, this might be one way you can all save yourself a few bob whilst driving around looking for work...
 
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The 3,000 mile oil change hasn't been relevant for years. It's only pushed by chain repair shops and unsuspecting folks fall prey.
 
A factor in all this is distance too. Do you drive a mix of motorway and city or country roads?
 
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i change my oil every 1200 to 2000 miles, but i cover that distance in a year, i use conventional oils, and i have a carbed classic car, in modern cars the 3000 mile oil change is a myth and unneccesary.
I saw a guy on a RAV4 forum that insisted that he wanted to change his oil every 2000 miles using full synthetic M1! Needless to say everybody told him it was ridiculous, i guy on a youtube video also insisted that you should change your oil every 1000 miles , and never use synthetics because they turn acidic, i sent him a link to bitog and told him to educate himself
 
3,000 mile oil may soon make a come with all these GDI engines coming to the market and stories about timing chains stretching
 
Originally Posted By: Ram01
3,000 mile oil may soon make a come with all these GDI engines coming to the market and stories about timing chains stretching


Why would oil change frequency affect timing chain stretch. That's a mechanical defect.


Most any conventional oil is more than capable of 3000 mile intervals.
 
Originally Posted By: mclasser
The 3,000 mile oil change hasn't been relevant for years. It's only pushed by chain repair shops and unsuspecting folks fall prey.


+100, but I'm sure even after we are all long gone, this 3000 mile OCI will still be in drilled into the heads of a large percentage of the world population.

The same applies for people that let their cars warm up for 5 minutes before they drive.
 
I think the 3k oil change is a product of early programming by oil companies, and the inherent conservatism of the American public.

That said, there are plenty of people that only change their oil when there is another problem with the vehicle.

Personally, it took a lllooonnnggg time for me to get past the 3k oil change. Back when I started owning vehicles, it wasn't all that short. But I am still way over conservative.....5k changes are as far as I have been able to move the ball.
 
To answer your question: the least expensive available.

Any modern oil (exception: those that PQIA has found to be not worth the container in which they are contained)

will be fine at 3000 mile intervals, regardless how the vehicle is used.
 
3k OCI=Marketing myth.

It's curious to me how gullible the 3k OCI folks are about oil intervals, yet they also don't extend the same logic to other fluids. How often do we hear the sanctimony of 3k OCI, yet those same folks never consider a brake fluid change or an ATF change?

I also take a bit of offence in the cultural arrogance and condescension of the question, as if somehow this is a USA only issue. The OP might want to take into consideration that this very forum seems to be disproportionately frequented by highly insightful Yanks who not only understand myth V. fact, but also have the cultural awareness not to insert that into the discussion.
 
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I change my oil per the manufacture recommended interval on all my vehicles. Don't listen to all that marketing junk.
 
I have seen the benefit if not need for 3k ocis in shared sump bikes that are run hard, combining synchromesh with 15k redline.
3k mi is also an acceptable oci for Mobil 2. Another can be water crossing mixed with severe duty, majority of driving in 2nd and 1st gears and lots of idle time.
 
Originally Posted By: Clevy
Originally Posted By: Ram01
3,000 mile oil may soon make a come with all these GDI engines coming to the market and stories about timing chains stretching


Why would oil change frequency affect timing chain stretch. That's a mechanical defect.


Most any conventional oil is more than capable of 3000 mile intervals.
Believe the chain "stretching" or link wear is caused by excessive shearing, & abrasive silicon & insolubles in the oil. I can think of a couple bad designs, too, some older Nissans & Mitsubishis didn't have the greatest chain guides.
 
Originally Posted By: Clevy
Originally Posted By: Ram01
3,000 mile oil may soon make a come with all these GDI engines coming to the market and stories about timing chains stretching


Why would oil change frequency affect timing chain stretch. That's a mechanical defect.


Most any conventional oil is more than capable of 3000 mile intervals.



IIRC
One of the reasons they reduced the OCI on the GM 3.6

Over-optimistic OLM = Timing chains "stretching".
 
Originally Posted By: Noey
3k OCI=Marketing myth.

It's curious to me how gullible the 3k OCI folks are about oil intervals, yet they also don't extend the same logic to other fluids. How often do we hear the sanctimony of 3k OCI, yet those same folks never consider a brake fluid change or an ATF change?

I also take a bit of offence in the cultural arrogance and condescension of the question, as if somehow this is a USA only issue. The OP might want to take into consideration that this very forum seems to be disproportionately frequented by highly insightful Yanks who not only understand myth V. fact, but also have the cultural awareness not to insert that into the discussion.


Oh dear, someone's got a thin skin...

For the record, this IS only a US issue. No-one else in the world has this weird fixation with dumping perfectly good oil way before time. Warped marketing message or not, a huge amount of you do still do it. Most of the rest of the civilised world is quite happy for oil to be black once it's in the sump. My old Toyota was doing 6k oil drains way back in 1990. I stretched that to 19k once (admittedly by accident) and the car still went on to do another 40k miles quite happily.

Sorry if you feel condescended to. It's probably rooted in a well justified, deep seated sense of inferiority. Hopefully it's a phase you'll grow out of...
 
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