I worked on a farm for a couple of summers that had a 730 diesel. I really fell in love with that tractor. I think that John Deere missed a good bet by not keeping it. This farm used to swap work with dad. Kind of adopted him when their father died. One summer we put the 4 row cultivator on our B John Deere to cultivate corn and sugar beets. The B used to go through about 15 gallons of gas in a good day. The next year put the cultivator on the 730. It would use about 5 to 7 gallons of fuel to do the same work. The other observation says something about an engine that is running at its torque peak rather than at its hp peak. We were filling silo and decided to use a gas powered 2020 John Deere to run the silo filler. The 730 was used to shuttle the wagons to and from the corn field. Both tractors were about the same hp, ie 55 - 58. I noticed that when the 2020 would get a slug of corn that it would start lugging down, and there wouldn't be enough air to keep the corn blowing up the pipe. So the corn would fall to the bottom of the pipe and plug the blower. I switched and put the 730 on the filler. When It would get a slug of corn it would just work a little harder without slowing down and the pipe wouldn't plug. Since the 730 was running at the torque peak it didn't have to slow down to get to the peak. Therefore it could pull through better. The philosophy on the new tractors is to get the hp through RPM. Forgetting that it is the torque that is the force to pull the load.