CutlassLegend

Has anyone tried or used the Rotella 10w30. I was thinking of switching from my conventional 10w30 to Rotella 10w30 for the added Zinc and price when compared to adding ZDDP. I am a little hesitant about using the 15w40 as my car has been on 10w30 its whole life and does not smoke or have any leak issues. Please let me know what you think.
Car is a 66 f85 deluxe with 330 LC 2v with 73,000 original miles and only driven as a cruiser, never hard. Your opinions are appreciated. If anyone know the zinc ppm for the 10w30 vs the 15w40 I would appreciate it.

rocketraider

I've always used the 15W40 simply because it was the easiest to find. Most any parts store stocks it. The 10W30 and sometimes even the straight 30 weight are not always easy to source.

I don't think you'll notice any difference using 15W40 vs 10W30 except maybe a little slower turning over in very cold temps. What you will see is the first few oil changes the Rotella is going to get dirty quick, because of its detergent action. Hey, the stuff is designed to control oil-borne soot in Diesel engines. I would use the best oil filter you can afford too, and not current production AC-Delco. A WIX or NAPA Gold at the very minimum.