What is the difference between the John Deere 9R 390 and 8R 410 Tractor?

Here is how the John Deere 9R 390 and John Deere 8R 410 Tractor compare on John Deere's published specifications:

• Horsepower: John Deere 9R 390 385 hp vs John Deere 8R 410 Tractor 404 hp
• Pto horsepower: John Deere 9R 390 335 hp vs John Deere 8R 410 Tractor 310 hp
• Weight: John Deere 9R 390 40660 lb. vs John Deere 8R 410 Tractor 28000 lb.
• Wheelbase: John Deere 9R 390 154 in. vs John Deere 8R 410 Tractor 120.1 in.