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Wi | The Sisu and Fendt CVT are flawless, you will love them. Very powerful, smooth, quiet and efficient. Very little issue with those two parts. One thing that seems to be an issue is people switching ranges too much. I think it may have to do with MF's location of the button and peoples natural tendancy to just think they need to be in low range if moving slow. You are better off leaving it in high all the time if you need the high speed, when you get to the field if you will be doing high draft work shift it down, if you are just spreading a load of manure you can just leave it in high. If you will be doing a lot of work at slow speeds and wont need the high speeds then leave it in low range. The high/low is synchronized and shifted with a dog clutch. Too much shifting on the go in the MF's will hurt this over time. The Tier 3 MF's allowed you to shift it when under a load which is very hard on it and causes a very harsh shift. MF controls the trans much differently than Fendt. Fendt does not allow the shift until the proper conditions are met then it will shift. Think of it like shifting to 4hi with an electric shift transfercase, it just blinks until conditions are right and then it engages. The Tier 4 MF's wouldn't allow shifts as easily but they would throw an error code everytime you tried to shift without meeting the parameters. It's best to just stop and shift it, there is not much need for shifting on the fly unless you are pulling tankers and such up large hills.
The confusion over the ranges is pretty common for some reason. The Fendt CVT is stepless all the way to 60kph(50kph in US). You can dial it into any 0.01mph that you choose from 0.01mph(60fph)-34mph(US). The Fendt CVT is simple, its a small planetary gearset (literally like 8") a variable displacement pump and two hydromotors as well as the range gears. The engine is always turning the planet gears in the planetary. The Sun gear drives the collector shaft which drives the range gear, the ring gear is connected to the hydro pump. The hydro motors also drive the collector shaft.. To start out, the pump swings to send fluid to the hydromotors which start out at full swing(45*), speed increases until the pump reaches maximum swing (45*). Then the motors start to swing towards 0* to speed the tractor up, this increases resistance on the ring gear and causes more power to go through the sun gear. When the motors reach 0* the power transfer is 100% mechanical through the sun gear. To get reverse they simply swing the pump the opposite direction up to 30* and the same philosophy applies.
With that concept in mind you can see how at low speeds power is transmitted hydraulically and at higher speeds it is more mechanical. By changing the range you allow the transmission to operate under less stress and also in a more mechanical more efficient state. It won't self destruct if you forget to downshift it for tillage or something. It does create added stress on it, but they still hold up fine.
The "ride" of the tractor is nice compared to our older tractors without suspension, but nowhere near the Fendt which I wouldn't expect due to the difference in systems. The Front axle suspension on the MF is similar to what CNH used on their stuff also. It works okay and does smooth things out. The Optiride is hit or miss. I wish Agco would've abandoned the idea and just went back to air. They used air on the on the DTa series tractors and the Valtra S series, which is the same platform as the 8600 series, uses air ride in place of the optiride. The Optiride uses hydraulic cylinders with accumulators at all four corners. It does dampen the ride when it works, but it's been plagued with a lot of issues. The Tier 4 models are much improved over the Tier 3. While it can be finnicky, its still far better than no cab suspension.
The A/C in the cab has issues keeping up and is very loud, there are some campaigns out to hopefully fix it right now but window tint is always effective.
As for hydraulic "output" I don't know, but they do have their share of hydraulic issues. I think they may be finally coming to an end and have the bugs worked out, but hydraulic and electrical gremlins are something that tend to plague them. The newer the machine you can get the better. For whatever reason the 8690s seem cursed with the most issues. As long as your machine gets all the updates and you have a dealer within a reasonable distance, you will like it.
What do you plan to use it for? Around here many have learned they are not ideal for dairy use, but for row crop work they seem to be great. | |
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Massey Ferguson 8680 advise and opinions wanted
