2.5 liter 4 cylinder, car is for a teacher, 34 miles a day, 17 miles one way to school and back. Fifteen of those miles will be at 70-75 mph. I was curious as to which oil to use, I had an '02 Altima, first year of the QR25DE engine, and it stated in the manual I could use anything from a 5W30 to a 10w30 and 10W40. for the 2008, it only says 5W30, but i think the other grades could be run. I was considering the following: Mobil 1 Advanced Fuel Economy 0W30, Mobil 1 Extended Performance 5w30, Mobil 1 0W40, or the Caterham blend (not sure to go with half and half, 60% TGMO, 40% Mobil 1 0W40 or vice versa.) Leaning towards just running 0W40, seen a few Altima used oil analysis with 0W40 and they turned out well, also heard Nissan engines are hard on oil. will do 6k ocis.