If you do find a solution please post it. I am having the same issues with my Z254 zero turn. It all seems to function normal until I engage the PTO. Then all the sudden its like I have went to turtle mode and the mower bogs down like its about to die soon as I hit a low patch of grass. Very frustrating because mine only has 2.2 hours on it and cannot get a response from Husqvarna.
Same issue here with the zero turn z254... I have even submitted the same basic question but still no answer from Husqvarna.