What kind of oil do ya'll run in your 300 I6? I have heard some people running delo 400le in these engines. What do ya'll think?

 

Some people do run diesel oil. Some of those oils have a higher zinc content, which is good for the old flat tappet lifters/cams that these engines use. Be warned though, you have to do some research to see which ones have the highest zinc content. Some diesel oils have lost their zinc content, and slowly but surely more and more are losing it. Do a web search for high zinc oils.

 

Take a look on this site.

The Petroleum Quality Institute of America