As I've been doing a lot of road trips (St. Louis area to Cleveland and back) I've definitely been trying to optimize fuel efficiency. I always keep up on plugs/wires, air filter, fuel filter, etc. Everything I can think of, and I always kept it at 65mph. I know that less RPM's x more MPH means fuel economy lol. I've found that 60 or 65 keeps it nice and efficient. Also with tire pressure... Definitely important. I have 205/45ZR17's on my EAP wheels, and I put 36psi in all four, I found it helps with the economy issue.
Thanks a lot for the insight on the oil, I'll definitely be considering what you mentioned when I make my purchase.