Changing oil less often is better for your engine - SAE

[buster]

Originally Posted by Patman
Here's the thing with this study that bothers me. That "aged oil" that supposedly shows lower engine wear, is also going to have contamination in it, especially direct injected applications that are dumping more fuel into it. So why would we want to leave our oil in longer when that's going on? Also, you can't possibly get every last drop of old oil out when you change it, there could be 10-15% of your total capacity left behind no matter how long you leave the drain plug off. I know with my Corvette, the manual says the capacity is 7 quarts, but when I refill it, the dipstick shows full with only 6 quarts added. So a lot is being left behind (I have seen pics of the oil pan and I believe a good half quart gets stuck in there alone) So my thought is that if the old oil helps "reactivate" the new oil, we don't really need to do anything different than we're already doing, as you'll always have that little bit of old oil doing it's job.


I agree. Like anything else, moderation. There is a sweet spot you can sometimes identify via a UOA with a particular oil/engine that you can go by.

 

[Kjmack]

Yesterday i went into my local auto parts store and asked for some used 2000 mile oil , they were out then i said how about 3000 mile ? Guy behind the counter looks at me wide eyed and said thats only for performance cars , what do you have ? Luckily while i was there a guy brought in a jug of old ATF , i grabbed it and didn't even care what it cost !

 

[Brigadier]

Originally Posted by madeej11
Brigadier, is that the best you can do. Ignorance is displayed in many ways, like buying that vehicle and ignoring to do your research. You never replied to that 90% thing either. That is ignorance.


LOL. You are really triggered!! WOW. So, the fact that my owner's manual says severe service OCI is 3750 is an indicator of a piece of junk? Is that what has your panties all twisted? LOL. Talk about ignorance.

I did a lot of research on reliability of various makes an models. I even asked my mechanic on what brand of vehicles they see the least of. Hyundai/KIA was at the top of his list. He sees the good, the bad, and the ugly of all makes an models. So I took his advice. Bought the V6 Santa Fe, and I am thoroughly impressed with it so far.

If having to change the oil every 3750 miles is the worst thing that I encounter, I will be ecstatic . If having to change your oil that often chaps your mangina, I don't know what to tell you.

And yes, I would bet that if you asked the manufacturer of your auto, they would say that you fall under severe service OCI, for 90% of the public.

 

[StevieC]

Originally Posted by buster
Originally Posted by Patman
Here's the thing with this study that bothers me. That "aged oil" that supposedly shows lower engine wear, is also going to have contamination in it, especially direct injected applications that are dumping more fuel into it. So why would we want to leave our oil in longer when that's going on? Also, you can't possibly get every last drop of old oil out when you change it, there could be 10-15% of your total capacity left behind no matter how long you leave the drain plug off. I know with my Corvette, the manual says the capacity is 7 quarts, but when I refill it, the dipstick shows full with only 6 quarts added. So a lot is being left behind (I have seen pics of the oil pan and I believe a good half quart gets stuck in there alone) So my thought is that if the old oil helps "reactivate" the new oil, we don't really need to do anything different than we're already doing, as you'll always have that little bit of old oil doing it's job.


I agree. Like anything else, moderation. There is a sweet spot you can sometimes identify via a UOA with a particular oil/engine that you can go by.

+1 to both of you. I would definitely do a UOA at least once to find out what the absolute limit is and then set my OCI below that so there is a margin for error. I would also do the UOA sometime in the cooler temperatures when the oil is a bit more stressed from short trips and richer fuel mapping due to the cooler temperatures.

 

[PimTac]

Originally Posted by Kjmack
Yesterday i went into my local auto parts store and asked for some used 2000 mile oil , they were out then i said how about 3000 mile ? Guy behind the counter looks at me wide eyed and said thats only for performance cars , what do you have ? Luckily while i was there a guy brought in a jug of old ATF , i grabbed it and didn't even care what it cost !





Good luck with your engine.

 

[RDY4WAR]

This discussion reminds me of my neighbor. He hasn't changed the oil in his Camry in over 4 years, but has put less than 10,000 miles on it in that same timeframe. He just changes the filter every 3 months and tops it off.

 

[ZeeOSix]

Originally Posted by RDY4WAR
This discussion reminds me of my neighbor. He hasn't changed the oil in his Camry in over 4 years, but has put less than 10,000 miles on it in that same timeframe. He just changes the filter every 3 months and tops it off.


No need to change an oil filter every 3 months, especially on a car that averages 208 miles a month. It's wild how some people take care of cars.

 

[RDY4WAR]

Originally Posted by ZeeOSix
Originally Posted by RDY4WAR
This discussion reminds me of my neighbor. He hasn't changed the oil in his Camry in over 4 years, but has put less than 10,000 miles on it in that same timeframe. He just changes the filter every 3 months and tops it off.


No need to change an oil filter every 3 months, especially on a car that averages 208 miles a month. It's wild how some people take care of cars.


That's what I said. His work commute is less than 4 miles round trip, and I know he doesn't let it warm up at all. Runs smooth and quiet.

 

[madeej11]

Originally Posted by Brigadier
Originally Posted by madeej11
Brigadier, is that the best you can do. Ignorance is displayed in many ways, like buying that vehicle and ignoring to do your research. You never replied to that 90% thing either. That is ignorance.


LOL. You are really triggered!! WOW. So, the fact that my owner's manual says severe service OCI is 3750 is an indicator of a piece of junk? Is that what has your panties all twisted? LOL. Talk about ignorance.

I did a lot of research on reliability of various makes an models. I even asked my mechanic on what brand of vehicles they see the least of. Hyundai/KIA was at the top of his list. He sees the good, the bad, and the ugly of all makes an models. So I took his advice. Bought the V6 Santa Fe, and I am thoroughly impressed with it so far.

If having to change the oil every 3750 miles is the worst thing that I encounter, I will be ecstatic . If having to change your oil that often chaps your mangina, I don't know what to tell you.

And yes, I would bet that if you asked the manufacturer of your auto, they would say that you fall under severe service OCI, for 90% of the public.

Of course if I asked any manufacturer. Of course they want to service your vehicle, we all know how conservative OEM's are, it's in their best interest to empty your wallet and cover their butts at the same time. Which reminds me, I've got 5k miles on my engine air filter, better swap it out now. Wow.

 

[Triple_Se7en]

Madeej
You chose to purchase a vehicle that may require either oil or air filters changes at 5K. So please blame yourself, not the manufacturer.
Lets not blame manufacturers for our choices in selecting vehicles with direct inject, turbos or mid/premium grade fuel requirements either.

Do your homework, prior to signing on the dotted line at the dealership.

 

[spasm3]

Back on subject, I have several questions about why wear goes up a bit after an oil change. I think dnewton3 has the same data.

Which of these things could it be, or a combination of all ?

1. Contamination introduced during the oil change?
2. Restarting the engine after the new filter is installed i.e. until the filter and oil circuits are filled.
3. Change in viscosity during the oil run vs the viscosity of the fresh oil?
4. Does the oil filter filter better over time as the media loads up, vs a new fresh filter?
5. Or is it the fresh oil and the Triblo layer on the metal surface being stripped and replaced?

 

[ZeeOSix]

Originally Posted by spasm3
Back on subject, I have several questions about why wear goes up a bit after an oil change. I think dnewton3 has the same data.

Which of these things could it be, or a combination of all ?

1. Contamination introduced during the oil change?
2. Restarting the engine after the new filter is installed i.e. until the filter and oil circuits are filled.
3. Change in viscosity during the oil run vs the viscosity of the fresh oil?
4. Does the oil filter filter better over time as the media loads up, vs a new fresh filter?
5. Or is it the fresh oil and the Triblo layer on the metal surface being stripped and replaced?


4. Oil filters don't become more efficient with use. Increased delta-p across the media due to debris loading can cause captured particles to slough off. Some filter media retains captured particles better than others.

5. That is the most likely reason why wear goes up with new oil, and what dnewton3 has mentioned in these same discussions.

 

[Shannow]

One of the posters showed his particle counts with new and used filters, showing that particle count stopped as filter loaded

 

[ZeeOSix]

Originally Posted by Shannow
One of the posters showed his particle counts with new and used filters, showing that particle count stopped as filter loaded


Link? I'd be interested in seeing the circumstances and data.

FYI ... data shown below is from Purolator/Mann+Hummel. Also, if you read the ISO 4548-12 efficiency test standard it shows the rated efficiency is the average of the beginning and end efficiency. Example below would therefore be ISO rated 75% @ 20 microns. So if an oil filter is rated at 99% @ 20 microns it can't really be a debris "shedder" as the delta-p increases. Could be the example you're talking about was a very high efficiency filter, and I could then see the PC not changing much if at all over it's use period.

 

[madeej11]

Trip7 you're not following the thread, I was just being sarcastic with Brigadier. Swap air filter at 5k? Not this century, not for me.

 

[Shannow]

Originally Posted by ZeeOSix
Originally Posted by Shannow
One of the posters showed his particle counts with new and used filters, showing that particle count stopped as filter loaded


Link? I'd be interested in seeing the circumstances and data.

FYI ... data shown below is from Purolator/Mann+Hummel. Also, if you read the ISO 4548-12 efficiency test standard it shows the rated efficiency is the average of the beginning and end efficiency. Example below would therefore be ISO rated 75% @ 20 microns. So if an oil filter is rated at 99% @ 20 microns it can't really be a debris "shedder" as the delta-p increases. Could be the example you're talking about was a very high efficiency filter, and I could then see the PC not changing much if at all over it's use period.

https://bobistheoilguy.com/forums/u...-filter-efficiency-over-time#Post4126540

 

[xtell]

Gentleman,

I don't mean to interrupt your discussion but I have a quick question. Why is motor oil so expensive in Canada. I live in Ohio and motor is is pretty cheep. This is a serious question, What's up with the high oil prices?

xtell.

 

[StevieC]

Originally Posted by xtell
Gentleman,

I don't mean to interrupt your discussion but I have a quick question. Why is motor oil so expensive in Canada. I live in Ohio and motor is is pretty cheep. This is a serious question, What's up with the high oil prices?

xtell.

Our dollar is worth 30% less than USD.

 

[ZeeOSix]

Originally Posted by Shannow
Originally Posted by ZeeOSix
Originally Posted by Shannow
One of the posters showed his particle counts with new and used filters, showing that particle count stopped as filter loaded


Link? I'd be interested in seeing the circumstances and data.

FYI ... data shown below is from Purolator/Mann+Hummel. Also, if you read the ISO 4548-12 efficiency test standard it shows the rated efficiency is the average of the beginning and end efficiency. Example below would therefore be ISO rated 75% @ 20 microns. So if an oil filter is rated at 99% @ 20 microns it can't really be a debris "shedder" as the delta-p increases. Could be the example you're talking about was a very high efficiency filter, and I could then see the PC not changing much if at all over it's use period.

https://bobistheoilguy.com/forums/u...-filter-efficiency-over-time#Post4126540


Going back through that thread, looks like that old 1965 SAE paper also concluded oil filters became less efficient as they loaded up - the "cake model of filtration" theory wasn't true. They only show the two first pages in the paper preview, but enough to see it parallels the Purolator/Mann+Hummel finding.

Not sure what to make of DrDaves PC data. Two PCs were only 54 miles apart. Who knows what kind of uncontrolled factors could have happened obtaining oil samples, etc.

 

[Patman]

Originally Posted by StevieC
Originally Posted by xtell
Gentleman,

I don't mean to interrupt your discussion but I have a quick question. Why is motor oil so expensive in Canada. I live in Ohio and motor is is pretty cheep. This is a serious question, What's up with the high oil prices?

xtell.

Our dollar is worth 30% less than USD.


True, and when you take that into consideration and look at some of the oil deals up here when sales kick in, we actually pay less for a lot of oils. For instance, a few weeks ago I got four 5L jugs of Castrol 0w40 for $27.99 CDN each, that works out to $21.27 US per jug. I used to buy all of my oil from Walmart in Niagara Falls NY, when I was using M1 in everything I grabbed a lot of those $22.88 jugs. But with the sales at Canadian Tire these days combined with the extra Canadian Tire money I earn with the new loyalty program, it makes more financial sense buying it up here now. Oil filters are still a bit cheaper in the US though, but only by a buck or so.