What is the difference between the John Deere S160 and S170?

Here is how the John Deere S160 and John Deere S170 compare on John Deere's published specifications:

• Wheelbase: John Deere S160 48.9 in. vs John Deere S170 48.9 in.
• Cutting width: John Deere S160 48 in. vs John Deere S170 48 in.