I have a 99 V-6 mustang and got it used it's in great shape but the only problem, I am having is I dont know what kind of oil the guy used in it. I was woundering if it will hurt to put what ever I want to in it. I am thinking about going with a high milage oil, but I dont want to screw up the motor if I change the oil going threw it. So what should I do?

 

Changing oil in midstream isn't the taboo it used to be.Go ahead and put in whatever kind of oil you choose.
Check the oil site in my sig for some real tech help with lubes of all kinds.