It is possible, I agree. If there's air in the system it has to come out for everything to work properly. Cycle the loader to it's full height and hold it there for about 15 seconds with the joystick in the raise position and pressure going over the relief valve. Same with the bucket curl and dump (both directions). That SHOULD get the air out if there is any. It might take a few tries if there's a lot of it. Don't hold it there too long, the oil will heat fairly quickly going over the relief constantly.
Sean