When oil has completed it's useful life, does it's color change?

[Stanley Rockafeller]

Case in point, my 97 Escort has about 8000kms on the oil and the oil still looks fine (full synthetic 5w30). Methinks I'll change the filter and top up with 1 liter of Valvoline since I still have a liter left over from the last change.
I was gonna try extending the OCI, but I don't wanna risk it and damage anything.
I've been running Acetone for the past 6-8 months and my last oil was Mobil 1 5w30 which I ran for a 20,000km OCI. (I was planning on selling the car, so I went with the Valvoline synthetic over the more $$ Mobil 1). Next change it's getting Mobil 1 from now on with my 20kms OCI's.

The Valvoline still looks pretty clean and not stinky at all...am I still OK?

TIA

 

[Vspec]

Really, there is no way to tell just by looking at the oil in my opinion.

If your planing to sell the car, who cares. If not i'd shorten the OCI's to 15 thousand miles with used oil analysis in between to see whats going on.

 

[Warstud]

I imaging it does in some applications where dirt and combustion is not a factor. When you say "usefull" do mean effectiveness? I think differential fluid changes to milky white when it loses it's effectiveness.

 

[Stanley Rockafeller]

exactly... I was thinking that the usefullness of the oil would be shortened, but then again, as long as the crankcase is clean, and the fuel system is clean, and the air intake is clean, an dfinally the engine is within spec of it[s internal parts...the oil should never get dirty (aside from som carbon washdown.)

 

[Achilles]

I wouldn't play around about guessing the condition of your oil by simply looking at it.
Castrol and Fuchs sometimes have a brown colour to begin with, and thats even before you throw it into the engine, its strongly not advisable to make calculated guesses.
However the "the one drop" oil tests are a good way to check, they measure the sludge in the oil and give reccomendations on the change intervals when for example the oil is "good", "ok, plan change", "bad, change".
Check it out, rather do that than have a busted motor because you were careless

 

[pajim17057]

Why are you running acetone? I've never heard of that.

 

[Terry]

Not necessarily Stan. Cleanliness,smell, and feel are subjective measures.

Knowing your engine/oil combo and what it normally looks like backed with UOA is a good measure for you to use.

Oil drop testing has some benefit for insolubles and fuel dilution testing.
There is one company I am looking at doing work for that is trying to get a lower cost and simple oil drop test system correlated to actual bench and UOA. It would be used by oil change places to verify duration of use and change intervals.

As always it just "depends".

 

[Stanley Rockafeller]

I gotcha, thanks guys!