In Reply to: New John Deere 8R series tractors and combines are coming posted by jd9750 on March 07, 2009 at 20:31:58:

Deere has such a heavy combine to begin with and much more weight and the rest of the frame and drivetrain probably can't handle it, warranty don't like to know about the huge bigtops now and they don't want to get into problems they have to repair at there expense.