John Deere 3038E Speedometer
I recently purchased a brand new John Deere 3038E and just realized that it does not show vehicle speed or miles per hour. The manual does not include the speedometer and I have called the dealer and John Deere with no luck. I have been told that the 3038R has a speedometer. How are you going to apply the fertilizer and use a sprayer without ground speed? The tractor is hydrostatic so the forward speed tables do not apply.
Google “Measuring Tractor Ground Speed for Fertilizer Spreading” and some results will give you some ways. For hydrostatic, use a set of rpm and cruise control on a course measured for distance, while than track the volume or weight of the fertilizer in one setting. There are, I believe, monitors that are available as well and maybe they can be rented or borrowed from a fertilizer farm store.
I had this same question and the solution in this post is what I did. I ordered and installed a cruise control kit. Part of calibrating sprayer tips (or measuring tip output) involves running and timing a predetermined distance. Now I set my RPM where I know it is supposed to be and smash the pedal going all the way to the floorboard and locking in the cruise control.