5W-30 or 10W-30 for a '71 383 2-BB

[scott0729]

This might be a dumb question, but I am trying to figure out which oil would be better for my engine. I have a case of Mobile 1 5W-30 oil, but wasn't sure if I would be better off using 10-W30 instead. Any opinions would be appreciated.

[RD]

matters on where you are located geographically if you want to get technical and what you plan on doing with the car; make sure you add a zinc additive.

[scott0729]

i live in south east wisconsin. for cold weather do i want a heavier oil?

[FLG]

You would want lighter oil for colder weather. As oil cools it thickens. Im in NY and just run Shell Rotella 15w-40 Diesel oil year round.

As RD said, its really matters what type of engine this is. Are we talking stock with millage on her or a brand new beast?

[scott0729]

stock, had 44k original, has since been rebuilt