How long before oil turns black

[AZjeff]

If you haven't owned a diesel you don't understand. SOP for most.

OP didn't even raise the possibility he was hosed. No need for confrontations or analyses.

 

[bullwinkle]

The inside of the average diesel, ESPECIALLY a CR Cummins, is coated with soot. Add a fresh load of high detergent HDEO, voila-black oil!

 

[CT Rob]

Originally Posted By: leeaspell
Had an oil change done recently on a 2012 ram 3500 with the cummins. Picked the truck up, drove the 3km home and checked the oil, it was as black as what was in it when I brought it there. I know it's a diesel and they turn the oil black fairly quickly, but that seemed really quick.
Both fords I've owned, a 6.4 and 6.7 would take about 1500km before it was as black as this stuff.
I have a 2005 Ram Cummins,and it turns black as soon as its started after an oil change has since it was new.113,000 miles and runs like a scalded cat.

 

[Dak27]

I've never owned a Dodge pickup with a Cummins motor or a PSD Ford, but I've owners F-250 HD's with the 6.9, and 7.3 diesel motors, and the oil in both would turn black within a day or two after an oil and oil filter change. What you're seeing sounds completely normal to me.

I did all my pm's myself, and I was pretty OCD about draining out the old oil; maybe a drop coming out a few times over a minute's time, before putting the drain plug back in, and adding the new oil.

I used mostly Delo 400 in both motors; I used Phillips Super HD-II, as well for about the last year I owned my 7.3, and the Phillips HDEO reacted exactly the same as the Delo; it turned black just as fast.

I'm a Truck Driver, and I've noticed this about the three big name diesel motors in Class 8 Semi Trucks:

Cummins ISX Motors: After a pm service, the oil was as black within the first day of operating it.

Detroit DD15 and Series 60 motors: The new oil stayed translucent for a couple of days before turning black.

Caterpillar 3406 and C15 motors: The oil stayed translucent for several days before turning black.

I hope this helps, and if it looks like you have a new filter(or filters)on your Cummins, I believe your oil was indeed changed.

 

[jongies3]

Normal on Cummins, I rarely see Cummins that aren't like this. Once in a blue moon you get those really clean ones but 9/10 they turn the oil black instantly. I've even filled them with oil and checked the level before starting and it was black already! I don't know why they do this, but it always felt off to me. They must be okay though, they seem to go for several hundred thousand miles like this.

 

[BrocLuno]

In most used engines, about 10 minutes