Take a look at the oil at 50 hrs . . . you'll be wanting to change it. As for the warranty issues, Deere even states in their manual: IMPORTANT: Avoid damage! Operating in extreme conditions may require more frequent service intervals. Engine components may become dirty or plugged when operating in extreme heat, dust or other severe conditions. Engine oil may lose efficiency if machine is operated constantly at slow or low engine speeds or with frequent short trips. I for one would rather be explaining how I serviced my tractor more frequently, than why I stretched out service intervals . . . /forums/images/graemlins/tongue.gif