What is the fuel capacity difference between the John Deere 6M 115 and 6R 120?

The John Deere 6M 115 has a fuel capacity of 46.2 gal. and the John Deere 6R 120 has a fuel capacity of 52.6 gal., a difference of 6.4 gal. The John Deere 6R 120 has the higher fuel capacity.