Exact same oil, but different color

[HawkeyeScott]

I just put in my last 6 qts. of old Havoline dino (bought nearly 3 yrs ago, FWIW) in my Jeep 4.0.

As I poured them put, 4 of the qts. looked one color, and two of them looked darker. Same 10w30 oil. All bought at the same store the same day and from the same apparent batch (all #s on the bottle the same). All quarts were unopened until yesterday.

Anyone have any idea why the exact same oil would be different colors, depending on which bottle it came out of?

 

[Scienceman]

Did you shake them?

 

[HawkeyeScott]

I did. I knew a few weeks ago I'd be using that oil, so I'd shaken them a few times since they've been on the shelf awhile. Most recent shake was last week. I did not shake them yesterday.

 

[mechtech2]

The code near the bottom will tell the tale. Black letters on a black bottle!
You may have a couple of 'Katrina' bottles, with relaxed standards concerning it's composition.
[because of the turmoil after Hurricane Katrina, oils were allowed more sulfur,and other laxities]

 

[Scienceman]

Its probally still ok oil for use though.