I have been changing my own oil now for about a year. No big deal. But, this time I noticed that the oil was blacker than usual. It had been about 7600 miles since my last change. No additives this time. I read in the owners manual that this might mean "fuel dilution." Is this something I should be worried about? Truck has just over 154K on it now. It runs fine with no problems. Oil pressure gauge fluctuates but I figured that was normal and never in the red.

Thanks.

 

Did you change the oil while the engine was still warm? Was the oil low? Any smell to the oil? When you drained the oil, any oil that has been dilluted will have a bluish/black or greenish/black color to it.

 

I'd be worried about fuel in it if you think it's really thin... does it smell like diesel? Did you use the right weight last oil change?

Get an oil analysis if you're worried. Blackstone labs are good people.

 

Yes, the engine was still warm. It did not smell of diesel at all. Nor did it smell burned or have any odor other than what oil normally smells like right out of the jug. I would say that in the light and on the rags it had a light shade of normal brownish color. I will look again when I get to the house again tonight but I did not see any greenish or blue coloration. I have always used Rotella 15 W 40.

I have a 30 mile commmute to work. I monitored the gauges all the way in this morning and saw no fluctuation out of the norm. I watch my fuel milage closely as well and have seen no change in that either; in fact it has gotten slightly better over the past couple of months, but I assume that is from the winter diesel was starting to thin out in the truck stop fuel stations.

This is the first oil change since changing the fuel filter again though.

Thanks for the help.