The V8 Owners Forum -

hi, got some oil from work, elf stuff and its rated at 5w30 is this to thin for a 3.9 with serp front cover. ill change it before the summer?

Yup too thin.

the workshop manual says 5w30 is ok for ambient temps from -30 to 35 deg c

For a serp. engine you want 10W40 or 15W40. Trust me, your oil is too thin, regardless of what your handbook says! You WILL cause rapid wear of the rear mains and big-end shells with an oil that thin.