A friend gave me a case of older SJ rated Valvoline 30 wt. HD oil...Is it OK to use in modern engines? I was going to use it in my truck this summer, Dodge 2500 5.7 liter.
Won't do any harm at all, in the summer, UNLESS your Hemi has the varible-displacement system (whatever they call it). That won't work 'properly' on anything but a 20-weight oil. Might want to check if you have that....
I'd run that SJ straight 30 in my '95 F150 4.9L any summer. I'd give you a buck a quart if you wanted to sell it. Problem is the shipping cost kills it.
