Well, it's that time and miles. My truck's second oil change is coming up but I am a little concerned because of the first week I owned it: had to make a few trips to the dealer for some post-buy stuff and during that time I got the worst miles to the tank: 163.:rant: With that in mind, I also changed the oil the first time to Valvoline SynPower full synthetic 10w-30 because, if my gas was that bad when I first bought my truck, then the oil the previous owner put in might have been some cheap ass shit they call oil that barely meets the minimum oil quality standards for conventional. My concern is that my engine could be sludged up now from the cleaning additives of the full synthetic, hence the reason I am going to the dealer for my oil change.