There is an optional "Deck Lock up Kit" available from JD for the 2520/2720 which allows you to mechanically lock the deck up, and still use the 3pth independently. It consists of 2 brackets that are mounted at the rear of the tractor near the 3pth arms, and 2 chains with turnbuckles, that fasten to the brackets and the deck lifting bracket, so you can adjust them. This set up will hold the deck up mechanically and still let you use the 3pth arms independently. I have a 54" blade for the snow, and I wanted to be able to hold up the deck arms independently, because I will also be using a ballast box in the winter for additional traction, and don't want to have to keep the box at the highest position when plowing snow.
Sort of a mickey mouse system, I thought it was going to be some sort of lever thingy that I could operate from the seat of the tractor, but no, just a set of "Limit Chains" that you have to pin to the brackets. It works, but as I said, kind of a mickey mouse deal, especially since here in Canada the kit cost me about $180.
I have a 2520 and ordered this kit with the tractor because I also wanted to be able to use the FEL while the deck was on, and didn't want to have to change lines from the FEL/Mower deck to the SCV ports, which you have to do if you have the independent lift kit, without the diverter vavle.
If you want to go with the independent lift kit and still use the FEL at the same time as the mower deck, you need to install the hydraulic diverter valve, which gives you 2 additional hydraulic connectors, and a push/pull control valve which is mounted on the lower right side of the operator station. This lets you keep all 6 lines connected at the same time.
By using the regular 3pth to lift the deck, you don't need the independent lift kit or the diverter valve so you can leave the 4 FEL lines hooked up all the time. Heck of a lot cheaper, especially when I read that the independent lift cylinder has a tendancy to leak down on it's own. Sure glad I went the way I did, would have cost me at least another $1200 to go with the Independent lift and diverter valve. I would have been some PO'd if after spending all that loot the thing still leaked down on it's own. Hey $180 sounds pretty cheap now that I think about it.
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