Why not run clean synthetic ALL the time?

[Rexman]

MinnesotaNole's question on oil color got me thinking about this one: What's wrong with having clean synthetic in your motor at *all* times?

By clean, we're talking "clean on your dipstick". Naturally, the oil will always look dirty when you drain it out, even after relatively short intervals.

The advantages would be:

1) Never having to worry about when your oil will start to get dirty. It's always clean!!

2) Possible extra savings in engine wear that we have never explored. Has anyone ever tried this to see how many miles they could make an engine last with *always clean* synthetic?

3) The satisfaction of knowing your oil is always protecting the engine at *maximum* ability. No worries about TBN depletion, oxidation, soot, or excess wear particles. The additives are always at near full-strength.

We think nothing of spending $3.50 a day for a premium coffee drink at Starbucks. What's the big deal about shelling out an extra $25-$30 a year for one more oil change that will ensure you're always running clean oil??

[ August 21, 2003, 03:42 PM: Message edited by: Rexman ]

 

[csandste]

Because cars are complex and engines are but one small part. Why pay extra for a 400,000 engine in a car that will only do 250K?

 

[Patman]

I guess this is a debate that will rage on forever. I know guys who change their synthetic oil every 4000km (2500 miles) and they say they do it because engines are expensive. Of course who's to say they are making their engine last any longer than someone who changes their oil every 8000 or 12000km? When we see oil analysis reports showing less than 5ppm of any of the wear metals and someone has gone 10,000 miles, how would they have benefitted from doing more frequent oil changes?

It's all a balancing act. From doing UOA you determine the safe point you can run your oil, and in most cases the reports show you could've gone a bit longer and still would not have seen a corresponding increase in wear (as viewed in ppm/1000 miles)

So sure, it won't hurt anything at all to continue doing 3000 mile oil changes even with synthetic. But in most cases, it's simply not necessary, the practice is not extending your engine life at all. You reach a point of diminishing returns, because you can't then turnaround and say you're going to double your engine's life by going from 3000 mile intervals to 1500 mile intervals.

One of the tests I plan to do next summer is take a sample of my oil at 3k, and then continue to run the same batch out to 6k, then compare the numbers. If the wear numbers have doubled, but not gone higher than that, then I know the 6k interval is safe. If I see the wear numbers triple compared to 3k, then I know I'm doing something wrong. I bet I'll find the 6k numbers are just as good (in ppm/1000mi) as the 3k numbers.

 

[csandste]

Your engine might last slightly longer if you changed your oil weekly. You might have less chance of getting colon cancer if someone scoped it every three months rather than every five years. Of course, every procedure carries its own risk, so at a certain point the risks of having an oil plug work loose or having your colon punctured would exceed the benefits of the extra procedures. Throw money into the equation and the cost/benefit ratios of doing too much to man or machine becomes clearer.

 

[JonS]

Just change the filter often and top it off. The new filter should clean up the oi along with the new oil upon topoff.

 

[Rexman]

quote:

---

Originally posted by cstandste:

Your engine might last slightly longer if you changed your oil weekly. You might have less chance of getting colon cancer if someone scoped it every three months rather than every five years. Of course, every procedure carries its own risk, so at a certain point the risks of having an oil plug work loose or having your colon punctured would exceed the benefits of the extra procedures.

---

Hmmm . . . changing your oil weekly--now THERE'S an idea!

With the new Fumoto drain valve, weekly oil changes could become a reality!

Whoops . . . please don't tell the guys at Oil-aholics Anonymous I said that!

[ August 21, 2003, 05:57 PM: Message edited by: Rexman ]

 

[3 Mad Ponchos]

I s'pose you could, if it makes you feel good to do it. I know leaving it in longer won't hurt anything, and I have priorities other than the cost of the oil that encourages me to extend the drain. It's not always about money.

Cheers, 3MP

 

[Rexman]

Ok, I guess most guys would probably agree with what's been stated here--to change it out before the oil is really used up is a waste of money and/or time, not to mention the oil itself.

But my concern is this:

When the oil gets past 3000 miles, the wear particles that are in suspension *become* part of the oil itself. When the engine is under load (fast acceleration, heavy pulling,etc.), the oil film separating the internal engine parts is *squeezed thinner* because of this extra load.

Now when the oil film becomes squeezed, the wear particles in suspension would then potentially cause more abrasion to bearings, journals, and other engine parts, would they not?
If you had changed out the oil at 3000 miles, these wear particles would have been removed from the engine.

So it comes down to the question of which would you rather have under conditions of heavy load when the highest engine wear can take place--oil with wear particles, combustion by-products, and more acids in it (the old oil that's continuing on from 3K to 6K) or brand new fresh oil (that was put in at 3K) that doesn't have any of this stuff in it.

[ August 21, 2003, 08:29 PM: Message edited by: Rexman ]

 

[mf150]

I will be changing my Mobil 1 supersyn 5W30 every 3,000 miles/3 mo.

I'm anal about my Stang's fluids.

 

[mf150]

To what Rex said,

the chemists take these wear metals, acid, etc. into account for the extended interval oils like Red Line, Amsoil, RP, Mobil 1. The chemicals neutralize most of the acids etc. maybe in conventional oil, you'd see this more?

 

[Al]

quote:

---

Originally posted by 3 Mad Ponchos:
I s'pose you could, if it makes you feel good to do it. I know leaving it in longer won't hurt anything, and I have priorities other than the cost of the oil that encourages me to extend the drain. It's not always about money.

Cheers, 3MP

---

I think this is exactly right. When do you determine that the oil is "clean" or "not clean"

Visually the darkness you see may be mild oxidation, mild soot and other things that may only have a micron size less than 1 micron. On the other hand you might us your "visual test" on another engine with very tight rings where tha oil may be wonderfully clean and yet has 100 ppm of lead and iron floating around (with particle sizes of 10 microns. )

So how did your "visual test work"

The visual test is about as useful the Jiffy Lube concept of changing oil every 3K .

I'll give you another example. My 01 Sentra keeps clean oil forever it just doesn't get dirty. Due to warranty considerations and "feel good" stuff-I'll change it around 6K miles.

My son's Cavalier will go over 11K miles. Oil is very dirty.

Shaeffer's 5W-30 Pure syn on both cars:
Cavalier(11100 miles)lead-7, Iron-13(Dirty oil)
Sentra (6700 miles)lead-11, Iron-29 (clean oil)
These are real life numbers. What say you??

 

[greencrew]

quote:

---

Originally posted by Rexman:
MinnesotaNole's question on oil color got me thinking about this one: What's wrong with having clean synthetic in your motor at *all* times?

---

Once you get past the oil pressure concerns and hiding wear material issue, that's my vision of the oil with a by-pass filter.

 

[greencrew]

quote:

---

Originally posted by Patman:
One of the tests I plan to do next summer is take a sample of my oil at 3k, and then continue to run the same batch out to 6k, then compare the numbers. If the wear numbers have doubled, but not gone higher than that, then I know the 6k interval is safe. If I see the wear numbers triple compared to 3k, then I know I'm doing something wrong. I bet I'll find the 6k numbers are just as good (in ppm/1000mi) as the 3k numbers.

---

That's it, right there, the number one question on my mind that I have not found the answer for. You just stated it a little differently than I did. I am expecting the 3k numbers to be less than half of the 6k numbers because I agree with what Rexman said about wear metals contributing to more wear metals.

Either way, I would hate to take a vacation and miss the results of that thread.

 

[GROUCHO MARX]

I work in NYC. It costs about 40 bucks a day to park the car. I just pull into a service station in the morning and ask them to change the oil(35 bucks). I pick up the car after work with fresh oil and filter every day at no extra cost!

 

[greencrew]

quote:

---

Originally posted by JonS:
Just change the filter often and top it off. The new filter should clean up the oi along with the new oil upon topoff.

---

Would that work? Wouldn't you still leave behind most of the particles smaller than 25 microns which would add up over time?

 

[Dan4510]

quote:

---

Originally posted by GROUCHO MARX:
I work in NYC. It costs about 40 bucks a day to park the car. I just pull into a service station in the morning and ask them to change the oil(35 bucks). I pick up the car after work with fresh oil and filter every day at no extra cost!

---

Groucho,

How often do you have to change a worn out oil drain plug?

Dan

 

[userfriendly]

Oil changes are cheaper than parking in NY NY?
That is the best answer I have ever read in any forum thus far.
Mine is the opposite end of the spectrum.
I have several vehicles. Some not so new beaters, along with a few toys. Expensive ones.
When my wood gettin' truck needs oil, it comes out of one of the toys or newer vehicles.
I don't buy new oil for my wrecks that are driven on dusty gravel and dirt roads.
Last month was a prime example.
My kid showed up with his Toyota 22R 4X4.
The oil was black, no UOA to confirm that it needed changing.
The Intrepid had about 1500 miles on a 15W40 HDMO which I drained and put into the 22R.
I park for free downtown.

 

[GROUCHO MARX]

userfriendly, et al.

I'm sorry, that's a story I remember lifting from another board many moons ago.

The truth is, you would be hard pressed to find 40 dollar parking at most times in NYC and service stations are even rarer on the isle of Manhattan.

At the North end of Manhattan at 215th street, there is a $13.95 oil change with a free car wash included.

Below 125th street, gas stations are few and far between, mostly exist on the edges of the Hudson and East rivers where the Taxis can gas up.

 

[Patman]

quote:

---

Originally posted by greencrew:

quote:

---

Originally posted by Patman:
One of the tests I plan to do next summer is take a sample of my oil at 3k, and then continue to run the same batch out to 6k, then compare the numbers. If the wear numbers have doubled, but not gone higher than that, then I know the 6k interval is safe. If I see the wear numbers triple compared to 3k, then I know I'm doing something wrong. I bet I'll find the 6k numbers are just as good (in ppm/1000mi) as the 3k numbers.

---

That's it, right there, the number one question on my mind that I have not found the answer for. You just stated it a little differently than I did. I am expecting the 3k numbers to be less than half of the 6k numbers because I agree with what Rexman said about wear metals contributing to more wear metals.

Either way, I would hate to take a vacation and miss the results of that thread.

---

We can also look at the data on 3MP's test to see how it goes. For example, let's look at his 3k, 6k and 9k data:

code:

---

3k 6k 9k

Iron 14 26 38

Lead 4 11 16

Alum 4 6 7

Copper 81 105 124

Chromium 1 2 2

Tin 4 4 4

---

In this case, we can see that most of the wear metals did not double and triple at 6k and 9k, other than lead. So that could be a concern there, but if others have similar data where they have a UOA at 3k and 6k on the same batch of oil, please post them here.

 

[3 Mad Ponchos]

If the premise is that wear metals contribute to more wear metals, then we have to not only consider the rate of wear but also the absolute particle count.

So far I'm at 15k and Terry Dyson still says the particle count is not hurting anything.

I liken it to "Yesterday there were four specks of dust in the house and today it's doubled. I'd better clean the house!" Sometimes a high rate of something only indicates that there's a whole lot of nothing going on.

Cheers, 3MP