I posted these way back when. They were for a different deere, but should be very similar to yours. By leaking I'm guessing you have oil leaking off the Breakaway Coupler. This can be fixed with the SCV on the tractor, but easier when you take it off. If you mean leaking like the valves are leaking(slow lift or lift by itself or lowers by itself) then the valves need changing. This is best done with the SCV off the tractor. There is also a seal kit available for them, but I bet that the valve itself is scorn and has to be replaced. There are 4 valves per SCV and they are not cheap. There is a way to test which one of the 4 is broken, but it involves a pressure guage 0-5000psi and a hose with a pioneer or JD coupler to stick into the breakaway. I can post the instructions if you like. Which model tractor?

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