A LCO friend of mine just got a brand new Toro Z Master and he thinks something is wrong with it. He mowed with it and he wears ear protection. Now he gets this very loud HUM that just after awhile makes his teeth hurt. He had an older style Toro Z and loved it. This one doesnt have an anti scalp wheel on one of the sides and it scalps while making a turn. He realy is unhappy with this mower. No he didnt demo the mower first since he has had a toro before. The dealer here dosent stock Zs either since in my area most lcos use JD tactors or JD Z. What could i have my friend checkout about the HUM. He is going to call the dealer and see if they can find out anything.