I've been researching this same topic for my ASV SR80. My controls also get very sluggish in cold weather, which makes me think that a previous owner may have put an incorrect/too-heavy oil in.
According to ASV tech support, the no-longer-available ASV Posi Lube was a multi-viscosity 5W-30...
I have a 2006 SR80 with some leaks at the plungers on the pilot control for the loader. ASV doesn't offer rebuild parts, just the whole joystick for $1000. Anybody know where to buy seal kits? The service manual lists the controls as Rexroth 08-351, which hasn't been especially helpful as far as...