Grasshopper 721d steering hard

Went to mow my lawn this morning and the steering on my Grasshopper is hard to move. It still cuts fine, but stopped mowing because I was concerned it may cause damage to continue.

Has anyone had this problem?

Thanks,

John

on my 928D there are grease zerts,pop you seat and look if there are zerts for the steering or if you have a manual look there....russ