loveurcar 
2002 Nissan Maxima Sedan SE 4dr Sedan (3.5L 6cyl 4A)
Worlds Best Synthetic Oil/Premium Gas/Air filter, 155K Still runs like the day I bought  w/ 56k
 Bought my Maxima in "06" and switched to Full synthetic oil within the 1st 3k-4k miles and have always ran Marathon/Speedway brand Premium gas almost always except for traveling on vacation. After studying more about syn. oil and air filters. I found that Amsoil syn. 0w-30, Amsoil oil filter, and a nano fiber air filter that they recommend that filters down to the smallest particle size(oil filter also) on the market that last 100k(vacuum every 25k) to keep your oil clean between 10k-12k between oil change intervals or once a year. I only have to add around 1 qt of oil between intervals. Since owning the car the MPG improved after switching to listed above to 30 mpg hwy and 27 average.