What is the difference between the John Deere 7R 270 and 8R 280 Tractor?

Here is how the John Deere 7R 270 and John Deere 8R 280 Tractor compare on John Deere's published specifications:

• Horsepower: John Deere 7R 270 266 hp vs John Deere 8R 280 Tractor 276 hp
• Pto horsepower: John Deere 7R 270 224 hp vs John Deere 8R 280 Tractor 228 hp
• Weight: John Deere 7R 270 25133 lb. vs John Deere 8R 280 Tractor 25800 lb.
• Wheelbase: John Deere 7R 270 115.2 in. vs John Deere 8R 280 Tractor 121.3 in.