Tim,
I have a 59 261. I sure I've always put 30w oil in most of the vehicles I've owned up until maybe 10 yrs ago.I realize technology has changed over the years and the oils may have improved. I had quite a few 325,230,250 6 bangers over the years and always did 30w, heck thats about the only thing that was available other than 40w and harley d 50w. I just noticed the other day when looking for oil that every place I looked there was no 30w.
