Hey fellow Tennessean. I also changed out the factory oil at 1,000 miles and went with Mobil 1 10w-30 and an AC Ultraguard Gold UPF-44 oil filter. This filter has the GM part#25329389. They are a bit hard to find and retail for around $8 but they're rated as one of the best oil filters you can buy. They not only filter (small microns) well but they have a great flow rate which is very important also. I won't argue all the opinions as to type and brand of oil to use but if you go the site bobistheoilguy.com you'll find more than you ever wanted to know about oil. These guys are petroleum engineers and are way over my head in their discussions but Mobil 1 does get a lot of positive comments. The oil filter from the factory is tightened way too tight so get a good filter wrench to wrestle it off. Good Luck.