Oil color

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All I ever read is...oil color doesn't mean anything.

Yet every time I see a car come in that has gone past what that car's oil change interval is supposed to be...or what that particular oil can handle...the oil looks black as night. So I think oil "color" is a term people are throwing around rather broadly.

For instance yesterday a car came in and the lady hadn't changed her oil in 10,000 miles (using conventional carquest 5w20). The car was a 2015 Kia Optima...15,000 miles. We did the first oil change to it at 5,000 miles in Septemeber. We did the next oil change to it yesterday at 15,000 miles. The oil was black, in fact after doing the oil change and checking the oil level I asked the techs...did you guys even change the oil? The oil on the dipstick looked terrible. They said yeah, you should have seen what came out of it. Then they showed me. Wow.

This was a little direct injection engine...low miles...basically a new car. Yet by going 5k miles past what that oil can handle, the oil appears to be black, dirty, nasty. And it still looks that way after doing an oil and filter change. And I see lots of oil changes - usually after a normal service interval oil looks pretty clear after that change.

So I think it's reasonable to correlate dirty oil to oil that is used up. At least that seems to be the correlation that I've witnessed with my own two eyes whenever I see cars go a bit too far on an oil that wasn't designed for it. I know an oil analysis would show you exactly what's going on, but doesn't common sense come into play? When the oil looks like it has so much soot in it that you can't see through it...and you know the person went too far on the oil change interval...aren't those two factors related? Doesn't "dirty oil" mean something? Anything? Or does everything have to be sent to Blackstone?
 
There's a car I'd pass on in the used car market. Does that sum up how I feel about oil color? LOL While it might not mean anything, anyone who knows anything about cars wants to pull the dipstick on a gasser and see black oil.
 
buying a used car first thing you look at is oil,color and smell..same for trans

most folks abuse what they own
 
The Kia owner is an idiot and the oil was full of dirt -- there's your answer.

It never ceases to amaze me how people can buy new cars and in good conscience never change the oil.
 
Originally Posted By: Excel
buying a used car first thing you look at is oil,color and smell..same for trans

most folks abuse what they own


Those are the first two things I check, oil and trans fluid levels and color. A fresh oil change can be suspect too, but there are other ways to tell if a car is truly well maintained or if someone is trying to hide something.
 
Is black oil due to soot ? Is that a sign the engine is running rich ?

I can never recall seeing the oil black after it has new oil & filter .

Could that also be an indication the filter is malfunctioning , or the pressure relief is bypassing the filter ?

Were this my car , I would never run it that long on dino oil , hopefully . But is so , I think I would run it for about 500 miles and change it again .

Should a 2015 Kia be running dino oil ?

Our 2015 Chevy Sonic calls for Dexos , which , as I understand it , is synthetic blend . I have been changing it 3,000 - 4,000 miles with the second tier Mobil synthetic .

Thanks ,
Wyr
God bless
 
Originally Posted By: demarpaint
Originally Posted By: Excel
buying a used car first thing you look at is oil,color and smell..same for trans

most folks abuse what they own


Those are the first two things I check, oil and trans fluid levels and color. A fresh oil change can be suspect too, but there are other ways to tell if a car is truly well maintained or if someone is trying to hide something.


like this I found last week


 
Sure, the oil may be have some soot and junk in there which makes it dark, but that doesn't mean the oil is "spent". It may still have plenty of lubricating life to it.

I owned a TDI diesel, after changing the oil with some golden colored fresh oil, I'd start it up, let it idle for 1 minute, turn it off and check the oil. It was JET BLACK.

You know how it looked under the valve cover? Absolutely clean as a whistle.
 
"but doesn't common sense come into play?"

Translucent or opaque?

I can't make sense out of used oil colors but you as a shop owner have a huge advantage. Do you go by color of used oil in a black drain pan, color of the oil stream as it's draining, or color of oil on a dipstick?
 
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Originally Posted By: Nick1994
Sure, the oil may be have some soot and junk in there which makes it dark, but that doesn't mean the oil is "spent". It may still have plenty of lubricating life to it.

I owned a TDI diesel, after changing the oil with some golden colored fresh oil, I'd start it up, let it idle for 1 minute, turn it off and check the oil. It was JET BLACK.

You know how it looked under the valve cover? Absolutely clean as a whistle.


+1

If the client told you it hasnt been changed the during the last 10,000 than you have reason to relate the color to being bad. Some cars turn oil black within a few thousand miles.. I highly doubt it means lack of maintenance. It all depends on the situation.
I agree with Merkava.. Beyond me how people buy new cars and neglect a simple (cheap) oil change.
 
Originally Posted By: Excel
Originally Posted By: demarpaint
Originally Posted By: Excel
buying a used car first thing you look at is oil,color and smell..same for trans

most folks abuse what they own


Those are the first two things I check, oil and trans fluid levels and color. A fresh oil change can be suspect too, but there are other ways to tell if a car is truly well maintained or if someone is trying to hide something.


like this I found last week






Wattttttt.. Wow...
 
10 k miles isn't much. ANY A3/ B4 would handle that without sweat, but mineral Api SN is SUBSTANDARD for 10k in little DI engine.
 
Originally Posted By: demarpaint
There's a car I'd pass on in the used car market. Does that sum up how I feel about oil color? LOL While it might not mean anything, anyone who knows anything about cars wants to pull the dipstick on a gasser and see black oil.


That's the first thing I thought when we were doing the service...I'd hate to be the guy buying this car coming off the lease. And I can see the dealership now...Certified Pre Owned Kia!! Just passed our rigorous 162 point inspection! One owner. Well cared for. Pride of ownership shows throughout.

Talked to the lady after and asked what she was doing, she said, I don't care it's just a lease. Be careful of leases people, I know they shine them up real nice at the dealer and hand you a clean carfax. There's more to them.
 
Originally Posted By: jorton
"but doesn't common sense come into play?"

Translucent or opaque?

I can't make sense out of used oil colors but you as a shop owner have a huge advantage. Do you go by color of used oil in a black drain pan, color of the oil stream as it's draining, or color of oil on a dipstick?


I went by what I normally see, what I normally see is oil that is changed at around 5,000 miles and it looks much lighter in color than the oil drained yesterday at 10,000 miles. And then when fresh oil is added to the crankcase, with a new filter and started. The oil on the dipstick generally looks clean/new.

Some oil changes stand out for the wrong reasons - this was one - when they pulled the plug it was black enough for a few techs to run over and check it out. And when I checked the oil level I wondered if it had been changed at all (and it had). This stuff isn't the norm at a busy shop...a lot of people use the synthetic or change the oil around 5,000 miles with conventional...maybe sooner.
 
Originally Posted By: chrisri
10 k miles isn't much. ANY A3/ B4 would handle that without sweat, but mineral Api SN is SUBSTANDARD for 10k in little DI engine.


but c2/c3 wouldn't... though they should. I see the same thing with the low and midsaps oils in petrols.

Diesels are a different story, they're always cleaner inside the crankcase/valve cover as gas engines are. These days at least.
 
Originally Posted By: Excel


like this I found last week






What did you find behind that spontaneous miscarriage? Inquiring minds want to know......
 
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Originally Posted By: demarpaint
Originally Posted By: Excel
buying a used car first thing you look at is oil,color and smell..same for trans

most folks abuse what they own


Those are the first two things I check, oil and trans fluid levels and color. A fresh oil change can be suspect too, but there are other ways to tell if a car is truly well maintained or if someone is trying to hide something.


Don't forget to take the oil cap OFF. You are looking for mustard or mayonnaise. That indicates mixing of fluids and is a bad sign. (Sometimes, condensation. Cold weather makes it hard to tell and you need to look for other signs.)
 
Originally Posted By: chrisri
10 k miles isn't much. ANY A3/ B4 would handle that without sweat, but mineral Api SN is SUBSTANDARD for 10k in little DI engine.


I agree, 5k miles on a mineral SN oil, with 10k or 12k miles on a high SAPS synthetic A3/B4 oil.
 
Originally Posted By: Merkava_4
The Kia owner is an idiot and the oil was full of dirt -- there's your answer.

Dirt? You're on a dirty kick, lately, Merk.
wink.gif
 
It's normal for diesel oil to turn black, but if you see black oil from a petrol engine, it has been in use for far too long. Most oil in petrol engines will change from the nice new gold colour to more of a brown colour by the end of the OCI.
Any signs of coffee cream on the dipstick can be real bad news, as that indicates coolant contamination (Normally from the HG, but can be from an oil cooler if the engine has one).
The oil in a petrol engine should stay the same colour as new for some time, if it turns darker straight away, there might have been some sludge in the sump.

Don't forget the sniff test, as the human nose can smell petrol contamination once it reaches about 5%.
 
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