I'm sure this issue has come up already, but I am too lazy to find it.
My dealer said I should change the synthetic 0w-20 every 4500 miles. Honestly, I have not reviewed the manual but that seems too soon. As a matter of numbers lets estimate that standard Nissan Altima 2.5L engine can provide an average of 30mpg combined highway + city http://www.fueleconomy.gov/feg/FEG20...neVehicles.pdf, on the NAH we are averaging say 40 mpg. My assumption is that, the 25% better fuel economy is due to the electric motors of the hybrid system. During the driving time that the ice is not "on" I will assume that the oil is not being deteriorated. So if I have driven a total of 4,000 miles, the ice has only been operating for about 3,000 miles, the other 1,000 miles came from the electric motors. My theory is that the actual miles driven are not the actual miles on the ice, so the oil change frequency should be adjusted for such. Any one of you math geniuses out there can please review my theory and my math.