Oil
Ken,
Perhaps I did not explain myself well.
What I meant to say, for engine: change at very first 1,000 miles to flush out all the metal from the break-in process, then again at 2,500 miles. From then on do it every 2,500 miles. This is cheap insurance.
For the final drive: Do the first change at 2,500 miles, again at 5,000 miles. From then on do it every 5,000 miles. What is the cost of a few ounces of oil? Also cheap insurance.
In the case of the engine, when you change the oil every 2,500 miles; the oil is still good, the problem is that the filter efficiency (Beat Ratio) starts to decay quickly, therefore, solid contaminants (ISO cleanliness code) in the oil are shooting through the roof.
Luis