Hydraulic Problem?

I have a grunt noise and the deck jumps a 1/2" or so each time it grunts. This only happens for about 3 min after initail start. After the tractor heats up all is good. It makes it hard to get the correct mowing height.

Try bleeding the system. Open the fill port in the reservoir and cycle the touch control 10-12 times. Should clear the air out of the system.

Also make sure that the system is full of fluid.