Regular oil from my dealership! I actually bought the 4 oil change package for $74.99, I buy them every year. I have a thing with wanting factory only maintenance on my truck. The only thing I have done, not at a dealership is breaks and tires and rotations. Before I had the air suspension I would buy the lifetime alignment at my local Firestone, but now I have the dealership, I have read too many horror stories on these fourmz about alignment problems.