Are extended drains really protecting the engine?

[bkbenjy]

Lest say you run the oil for 3000 miles.
Then you get a used oil analysis and it shows you have 5 iron, 5 copper, and 2 lead.
Now lets say you didn't change that oil and continued running it. Wouldn't the copper, iron and lead be circulating in the engine and scratching out even more metal?

Theoretically an oil that has 6000miles on it will have double the metals of the oil with 3000 miles. That's assuming same 0il and driving technique. But isn't it possible that the oil would have substantially more than double the metals?

So is it really worth it to run extended drains. If two 3000 mile oil changes have less combined wear than one 6000 mile oil change?

 

[JAG]

Apparently the wear metals don't contribute much to 3-body abrasive wear in typical scenarios. Don't worry about that.

 

[iunderpressure]

You could change your oil every 1,500 miles or every 2 weeks, but that would get expense and be a waste of a lot of time

 

[BobFout]

IIRC, wear metals are an effect of wear, not a cause of wear.

 

[wannafbody]

They are too small for a filter to trap so I doubt they cause any measurable wear.

 

[tom slick]

If the wear particles at 3000 miles were causing MORE wear than the particles at 1500 miles (because there are more particles in circulation) then the relationship would be more than double; it would go up exponentially.

That just isn't the case when you look at the oil analysis reports.

 

[Pablo]

The 5 ppm Fe, Cu, Pb are representative of wear metals but are not necessarily wear metals. To be detected, as PPM, the metal must be soluble in the oil. Chunks and other particles of size, (which above a certain size will cause damage) are not detected in simple $25 used oil analysis - because they simply are not in solution. Just because an oil is used for 10K, 15K, 25K, does not mean there are any more of these larger particles than oil changed every 3K. (assuming the AF is functioning!)

 

[stenerson]

Proofs in the pudding. Many here have done 100s of thousands on extended drains with good results.

 

[tig1]

You are putting too much stock in used oil analysis. You are talking a few PPM. That's nothing. I've run 10K OCIs for 32 years with never an engine failure or even even an engine beginning to show wear.

 

[ARB1977]

I dont know why but it seems my engines run smoother as the more miles i put on an oil.

 

[cchase]

Originally Posted By: ARB1977
I dont know why but it seems my engines run smoother as the more miles i put on an oil.


I have the exact opposite experience. Fresh oil always feels smooth to me. Very noticeable difference.

 

[demarpaint]

Originally Posted By: cchase
Originally Posted By: ARB1977
I dont know why but it seems my engines run smoother as the more miles i put on an oil.


I have the exact opposite experience. Fresh oil always feels smooth to me. Very noticeable difference.



I notice a difference with fresh oil too, maybe the fresh oil is thinner, and that's what we're noticing? I never did a used oil analysis so I don't know if that is in fact the case.

 

[lexus114]

Originally Posted By: cchase
Originally Posted By: ARB1977
I dont know why but it seems my engines run smoother as the more miles i put on an oil.


I have the exact opposite experience. Fresh oil always feels smooth to me. Very noticeable difference.


+1

 

[tig1]

Originally Posted By: cchase
Originally Posted By: ARB1977
I dont know why but it seems my engines run smoother as the more miles i put on an oil.


I have the exact opposite experience. Fresh oil always feels smooth to me. Very noticeable difference.


I just changed the oil in the Focus last week with a 10,000 mile OCI, and I didn't notice one witt of a differance after the change.

 

[lexus114]

10,000 miles huh? your crazy.

 

[Steve S]

I have seen lots of high mile engines run extended oil change intervals run on oils designed for extended oil change intervals. I depends on how the engine was used.

 

[tig1]

Originally Posted By: lexus114
10,000 miles huh? your crazy.



Well I have had plenty of experience with 10K OCIs and have never saw any differance.

 

[BobFout]

Originally Posted By: lexus114
10,000 miles huh? your crazy.


Our European friends laugh when we [Americans] say things like this.

 

[JeffGoji]

Originally Posted By: demarpaint
Originally Posted By: cchase
Originally Posted By: ARB1977
I dont know why but it seems my engines run smoother as the more miles i put on an oil.


I have the exact opposite experience. Fresh oil always feels smooth to me. Very noticeable difference.



I notice a difference with fresh oil too, maybe the fresh oil is thinner, and that's what we're noticing? I never did a used oil analysis so I don't know if that is in fact the case.



Most likely, a placebo effect in both cases.

However, with some engines and oil brands and weights, it's possible for the oil to sheer down to a lesser grade and cause more mechanical noise to be heard as the miles stack up.

By that same token, it's also possible for some combination of engine oil brands and weight and engines to thicken up and out of grade as you rack up the miles.

So you both could be right.

 

[JeffGoji]

Originally Posted By: lexus114
10,000 miles huh? your crazy.


How so?