The operators manual that came with my X-ONE is very specific about SAE 20W50 SL/SM for the Hustler X-ONE. Then next sentence says use only 15W50 Mobil One for the Super Z as the manual covers both models. Soon I will do the 50 HR hydraulic system oil/filter change on my new X-ONE. I just ordered the parts needed and a set of blades from the selling dealer. This machine has a 60" rear discharge deck with blades that are not as common as side discharge decks.
I strongly recommend to everyone that has purchased a new or used machine of any make, to read and understand the operators manuals, many of which can be found on line if a manual didn't come with the machine.
For one of my customers I have blocked out or crossed out all the information in his operators manual that doesn't pertain to his specific machine to reduce confusion as he has a vision problem.
Bob MacGregor in CT