what kind of oil goes in a 1951 ford f1 with a flat head v8?

[Pat G]

I looked at the oil and it is BLACK i got a new filter but i don't know what kind of oil to put in it i heard either 15w40 or straight 30 weight.

[wizerdauto]

i recomend 30 wt, prefferably non detergent but it is about obsolete due to emission regulations so you'll just have to use sae 30 wt.
I recomend valvoline motor oil

[Pilsner Man]

You can use 10W40, with all the slop that is probably in the engine.

Here's what I would suggest though. Drain the oil, put the new filter on and put 4-5 qts of transmission fluid in it. Run it for about 5 minutes and drain it. This is an old motor cleaning trick.

Then put a new filter and fresh oil in it.

I would also start putting money away to do a rebuild or find another motor.

[Oldschooljeep48]

If it runs great with no leaks, straight 30 weight. if she leaks a little bit and it doesn't get too cold where you live (under 20*) then go 10-40, or straight 40.

Keep her going!