You've got to love marketing. There are lots of little things that change in addition to HP. The economy PTO is one of them. On the 4720 the air cushion seat is "standard" instead of optional.
I would guess that the engines have different sizes of some components that are "bolted on" to the main block. I can see differences in turbo sizes, fuel pumps, injectors, and things like that which, in conjunction with software, make the power differences. Don't bother telling me if I've got the details wrong :laughing:! The point here is it seems really unlikely that the engines are exactly the same in all of the lineup, and it is really only a software change.
And of course the cab is only available in the top 3 sizes. Now that (and a lot of these other things) is not all 100% marking driven. The AC on the cab takes power from the engine, so there is some logic to having it available on only the higher HP models. I'm sure the engine differences/changes are also commensurate with the HP.
I think the economy PTO is in the same boat. Offering it only in the higher HP models lets you command a higher price. But it also makes sense that as the PTO HP increases, there will be more times when you might use a lower HP attachment and the E-PTO makes sense. My sickle bar mower is very happy on the E-PTO. I'm not feeding it too much power, tractor runs at lower RPM, uses less fuel. Then, when I have the MX6 rotary cutter on and am in heavy grass, I need the full HP of the machine.
Years ago, I ordered large french fries at a fast food place. Got small. Pointed out the error. The worker dumped the small fries into a large fry container. Talked with manager who apologized and fixed the problem. So even marketing guys are smart enough to have acceptable reasons for all the models and different offerings. It's not much different than some of the car lines that are "good - better - best". Trying to figure out if the pricing and features are "fair", or engage in some silly game of just buying the tractor with the worst margin thinking it's the best value will just eat you up. Manufactures are far better at this game than you or I will ever be. So just look at the features, cost, and get what you need and can afford.
I think you could cut about half of the Deere product out of the lineup and it would still be just great. It seems like having horsepower available in 10% increments as you move through the line is too small of an increment. Can you really tell the difference between a 25 and a 27.5 HP tractor? Or in the 4000 series, between 60 and 66 HP? I'm sure some can, but bet most can't.
Marketing types are like the people who kind/stupid enough to introduce themselves and say they are "basically honest". You know there is something not quite right going on, but there is just enough of a good reason behind what they say that you can't call them on it.
At any rate, I doubt the only difference in the 4000 series is the small fry bag was dumped into the large fry container. People are stupid, but not that stupid, and we're talkin' tractor owners here who are clearly a cut above the grade, yes
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Pete
