What wieght oil do you use?

I run castrol 25-50 in the Demon...Till next change then itll be 50W val. racing, Mustang No idea till the next change in the next few days and itll have val. 50W too. Ramcharger has quaker state 10-40 4X4 and SUV Heavy duty senthedic........Nova I have no Idea It might not have any in it lol.......