Paul: Since the transmission is not synchromesh, you must try and achive having the input and output shafts of the transmission near the right speed for the gear you are going to, at time of engagement. This becomes quite easy with 1, 2, 3 and 4 as they are quite close to one another, whereas 4th and 5th have wider range between speeds. 5th basically is a road gear and one must remember the evolution of this. Most tractors of the 20s and 30s did not even have the road gear, being sold on steel. Early letter series Farmalls had a device for blocking 5th gear if tractor was sold on steel wheels. Letter series tractors shifted from 4th to 5th somewhat better before the days of TA. With TA you have two clutches having to operate simultaneously as you shift gears. If that adjustment is not dead on this adds diffculty. In my experience with new Farmalls 300 and 560, 40 to 50 year ago, I never shifted from 4th to 5th on the move. Those tractors would start away on level or down grade, in low side of TA in 5th gear, with any load they could pull in 5th gear along the road. If you were on the upgrade, you contented yourself to 4th until you reached top of hill. These afterall where tractors, primarily designed for pulling plows, cultivators, mowers, balers, drills, corn planters, etc. They were not race cars, automoblies, motorcycles or trucks. In my opinion the new breed of users have destroyed the most efficient drawbar tractors we ever farmed with. Rather than a rugged transmissions and engines with big displacment and high torque, they wanted smooth shifting, power shifting, etc. They turned every tractor into a loader tractor or something to chase the cows with. I can remember the days when you put a Farmall in gear in morning, 12 hours later you were still in same gear. It lugged through all the tough spots without shifting. I have driven new tractors in the past 5 years, tractors all the way from 40 to 250 hp, all makes, they've got no torque, you need a minamum of 4 power shifts to do anything. You compare the cost of one of these new transmissions with your 300 (same size tractor), then compare the return on the commodities they produce 1950s prices with 2005 prices.
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