PTO MAINTAINANCE AND COLD WEATHER

First thing I would do is replace both hydraulic filters.
I change them every year as condensation gets in the filters and when it is bad the cylinders will act like you are experiencing. While you are under there doing the hydraulic filters replace your air dryer filter. (Drain all air first). I do all 3 filters my last service before cold weather hits. I also gradually switched over to the thinner 32 Hydraulic fluid from the 46 that it came from Cottrell with. You can buy it in a 5 gallon pail and mix it with what you currently have in it.

 

Side note that may not effect you but others it may. If you have an empty deck that struggles to come down you likely have rusted metal clogged up inside the post. My high rail once did this on the back top deck. It had holes at the bottom of the post that were designed to wash out the rust. Spray PB Blaster form the top of the post to the bottom and let it sit for a while. Then hose the rust/metal out from the top down and make sure the water is flowing freely.

 

In addition to what @Banker recommended, you might consider changing out the hydraulic fluid. It sounds like the entire system may be carrying water.

 

In the bottom of the outside upright tube, drill holes so the water can drain out. Grind down and slip plate the inner tube. Occasionally spray the inner tube with antifreeze so the water will not freeze.