What is the difference between the John Deere 8R 440 and 8R 490?

Here is how the John Deere 8R 440 and John Deere 8R 490 compare on John Deere's published specifications:

• Weight: John Deere 8R 440 37377 lb. vs John Deere 8R 490 37377 lb.
• Wheelbase: John Deere 8R 440 131.9 in. vs John Deere 8R 490 131.9 in.