what kind of oil

What does your owners manual say? It is best that you do not second guess the people that engineered your car. My guess is it is probably 5W-30 but look at the manual. I would use a synthetic oil such as Mobil 1 if it was my vehicle. My experience with it in vehicles with high and low miles has been great.

most vehicles have different thicknesses depending where you live if the climate is very cold then 5w 20 would do for the winter, if in warm climate 20w 30 is better. if the engine has seen a lot of miles them 20 w 40 would be best. but the normal oil is 20 w 30.

It requires 5w30, but you may substitute with 10w30. Factory man was right on with the Mobil1 suggestion. GM requires Mobil1 synthetic oil in their high performance engines due to its unbeatable performance.

I guess it comes down to what you want to spend for oil, at most of the oil changes around here they use vavoline 10w 30 sythetic oils are good just how much you want to spend.