Looking at the owners manual I do not find a spec for the amount or a listing of the recommended grade or type of gear oil. I can think of a coupe of reasons why the worst being it is never meant to be changed (there is no such thing as a lifetime lubricant) or possible it is drained and filled until it is topped up. What is the insider info on this. I would like to change along with the engine oil at 1-2K. Lovin' my two day old Pearl White Sport, the paint is really nice and the ride which was pretty rough is starting to smooth out. When I got it delivered they put 30 front and 35 rear and setting the tires to spec actually made the ride better, headlights are now aimed correctly.