blackish engine oil
 

I change oils a couple 3 months ago. Used Pennzoil. Truck driven since only a few miles. Oil blackish again. I'll check as to what oil I used. detergent I think 10W40

Re: blackish engine oil
 

Hey, the oil in these old engines gets "blackish" pretty darned quick. I wouldn't worry about it. Check the level often and change after 1K miles more or less.

Re: blackish engine oil
 

What temperature does the engine run at? A hot engine will
make the oil black. G.M.

Re: blackish engine oil
 

Detergent oil turning dark is normal. If the oil is "blackish" it could be from the carb running too rich. Even if no black smoke is seen coming out the tailpipes, the mixture can be so rich that excess fuel ends up in the oil.

Re: blackish engine oil
 

Think I'll agree with Lawson. But I will say when it goes black change it again and repeat. Once you can run oil for a couple weeks and months and it still looks like when you poured it out the bottle. Let me know how you did it.

Re: blackish engine oil
 

detergent oil goes black its actually carbon or sludge suspended in the oil [its normal] keep changing it regularly and it will eventually remove all the sludge built up inside the eng great if its in good nick with low wear not so if high mileage and high wear as it will start to burn oil and leak as the built up crud is slowly washed out [thats what gave detergent oils a bad name ] Modern detergent oil are probably more stable than mineral oils will ever be but they have their limits they wont cause wear but wont fix wear thats already there

Re: blackish engine oil
 

It will still be doing it’s job fine, clean oil with high miles with worn out activities is the one to look out for, I made that mistake when I was younger and thought younonly changed it when it got black.

Re: blackish engine oil
 

Folk are growing used to the modern computer controlled cars that are so efficient that the oil takes a long time to darken and last for longer periods for scheduled oil changes. Electronic fuel injection is mandatory in most all internal combustion engines with the exception of small engines. Modern oil filtration systems don't have to work very hard to clean the byproduct of this efficiency level.