I have a 2008 asv sr80 that is having problems on the boom lift circuit. It is weak lifting and as I pull the joystick back to boom lift the first 20% of that motion puts it into a "float" and the boom drops until I continue to pull it back thru that then it starts to lift. Also when the boom is all the way lowered and I joystick forward to lower boom down against the stops the left side torques up a small amount almost like that cylinder is trying to raise. I did the pressure tests asrecommended by the manual, all good but boom up. All other functions max out the pressure at idle when stroking out the cylinders except boom lift. It sits about 1400psi at idle and will go up to 2450 at max throttle. It should be 3000 like all otherfunctions are. I replace that relief valve and no change. I tried adjusting both old and new relief valves and no change higher. Iunpinned the right boom lift cylinder and raised boom all the way up, same pressures. When I went all the way down against the stop with only the left lift cyl. attached the boom jumped up and down about an inch fairly violently while holding joystick on boom down. Sorry for the long story but wanted to give good info. Any help would be appreciated.