Miles vs Hours: visual oil experiment

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Here are the samples of the same oil (Toyota 5w30) from different OCIs and different duty cycles in the same engine.
-Sample on the very left is a brand new oil.
-Next one to the right has 10k kilometers (6200 miles) and 294 hours of mixed driving.
-Third sample has 16k kilometers (10k miles) and 307 hours of highway cruising.
-The darkest sample on the right has ONLY 8.5K kilometers (5.3K miles) and 354 hours of city traffic with idling and stop&go.

Of course a UOA would show a bigger picture, but oil color does give a good idea of how used up the oil is. Free visual oil analysis, so to say.

 
Interesting, thanks for posting. The only flaw I see is the last sample is from the engine with over 21K miles more on it than it had when the first sample was taken. More wear, etc.
 
Originally Posted By: demarpaint
Interesting, thanks for posting. The only flaw I see is the last sample is from the engine with over 21K miles more on it than it had when the first sample was taken. More wear, etc.


Samples were taken in this order:
1) 6200 miles
2) 5300 miles
3) 10000 miles
 
Originally Posted By: Vlad_the_Russian
Originally Posted By: demarpaint
Interesting, thanks for posting. The only flaw I see is the last sample is from the engine with over 21K miles more on it than it had when the first sample was taken. More wear, etc.


Samples were taken in this order:
1) 6200 miles
2) 5300 miles
3) 10000 miles



OK, but each time a sample was taken the engine had more miles and more wear on it. I'd also expect the oil with the most time on it and hardest use would be the worst, which the picture shows.
 
Originally Posted By: Vlad_the_Russian
Of course a UOA would show a bigger picture, but oil color does give a good idea of how used up the oil is. Free visual oil analysis, so to say.

So you can tell how "used up" it is by the color?
 
Originally Posted By: Vlad_the_Russian
Here are the samples of the same oil (Toyota 5w30) from different OCIs and different duty cycles in the same engine.
-Sample on the very left is a brand new oil.
-Next one to the right has 10k kilometers (6200 miles) and 294 hours of mixed driving.
-Third sample has 16k kilometers (10k miles) and 307 hours of highway cruising.
-The darkest sample on the right has ONLY 8.5K kilometers (5.3K miles) and 354 hours of city traffic with idling and stop&go.

Of course a UOA would show a bigger picture, but oil color does give a good idea of how used up the oil is. Free visual oil analysis, so to say.




This is useless. Assuming there are no obvious mechanical problems with the engine (like a head gasket leaking antifreeze into the oil), the only thing that can be determined by the color of the oil is the color of the oil. I have a UOA on this oil:

Would anyone care to guess at the TBN, wear metals, Iron ppm, viscosity, miles, ISO 4406 particle count, etc?

This oil has over 8K on it and test lab results are "suitable for continued use." All parameters normal from the test lab.

The color of the oil reveals NOTHING except the color of the oil. I have sent in previous samples that "looked nicely honey colored" and were contaminated with coolant. (High Potassium ppm). It is my opinion that UOA has saved more than one engine for me. There isn't a Mr. Goodwrench mechanic in the nation who could have looked at my oil on the dipstick and said "Gee, Mister, 446 ppm Potassium, you've got a coolant leak."
 
Originally Posted By: Ihatetochangeoil
The color of the oil reveals NOTHING except the color of the oil.


Quoted for truth...

I sponsored a thesis on optical patch colorimetry on turbine oils a few years ago.

With that, t-you take the oil, thin it with solvents, run it through a 0.5um filter paper, wash the oil residue out with a non polar solvent, and then compare the colour on the patch with a reference of virgin oil...yes, it tracks varnish and oxidation pretty well...if we could have done it with a test-tube, clearly industry would have developed that instead.
 
If it never ever changed color or went black instantly then it would have zero meaning. I bet dollars to donuts if you pulled the stick out of a car you were thinking of buying and it was jet black it would make you go hmmmm. Then you open up the oil cap to see what or if you could see into that.
Color is not definitive that is very true. But it does change with time and type of use. And by this we can see at least if it's jet black or golden brown, or translucent. If some cat swears the just changed it on a gasoline motor and it is jet black we'd know they are full of number two. This would have us question if they were telling the truth about them saying it was maintained well by them. When I went 11k miles on my Castrol Syntec in my old Sentra it was just about jet black. Unlike the usual slightly dark brown it was when I normally changed it at 4500 miles.
 
" Of course a UOA would show a bigger picture, but oil color does give a good idea of how used up the oil is."

Even on the longest OCIs I ever dared, the oil was never "used up", darkness in oil from a late model engines will
be all the various metals that wear off, in very old engines you can include soot and combustion by products. Some
additives did deplete, but not 80% like I thought, more like 20-40%!

Why?

Once I changed over to a pair of FilterMags and a bunch of other magnets on the spin-on oil filter my oil stays
clear for months and 9,000Kms / 5,500 miles before it even start to turn dark! Was I surprised!


FILTERMAG vs HOMEBREW
https://app.box.com/s/uxvu8dmscf5wcgftutdm0ejqwgn86tw7
 
I agree. A more in depth analysis is certainly needed to assess what the real condition the oil is truly in. Agree 100% on that. You can't tell TBN, viscosity at 100°C, what else is present in it has well by color. But it does change with time as well in a gas motor.
 
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Slightly off track but wouldn't it be something to have test strips much like blood glucose strips that would test for TBN, fuel, oxidation, etc? Maybe they do have these but I am not aware of them.
 
Originally Posted By: Ammofirst
“Nothing” ?


NOTHING ...other than the color of the oil...

OK guys...I'm coming up on 40K without an oil change (I'm running more than one bypass filter in series); Blackstone says I'm fine.

I'll photograph my 40K oil sample with my same (light pink) kitchen counter for a backdrop, just like the above picture, and we can see who can tell the 8K oil sample from the 40K oil sample. Place your bets.
 
I like the OP's sampling. For his oil and his car, color does have some meaning. With my cars, maybe no so much. Seems most of my oils turn black'ish before 5,000 miles, so I have lost the color check capability. But that clean little Toy he drives seems to gradually darken by abuse, so that's a good one
smile.gif
 
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