The brand of oil you use is more a personal choice than any thing else. Although motor oils are formulated differently the fact of the matter is that when it comes to protection they are all about the same. Synthetic oil is the best but don’t put it in an old motor because oil leaks have been known to happen. When I was building race cars we used Castrol GTX so that is what I recommend and use in my car to this day. I have never had an oil related problem since I started using Castrol. You should use a heavier oil in the summer like 30-60 and thinner oil in the winter 10-40. Thicker oil helps to cool the motor and thinner oil helps it to worm up faster.