Here are the main changes for the 2015 John Deere 1775 Planter with Max Emerge 5 row units:
Ability to run cable drive and granular insecticide. Can run with 1.6 or mini hopper and cable drive.
Gauge wheel arm bushings much more durable because of smooth bushings rather than full thread-much longer life
Double eliminator is adjustable from outside the meter with a knob and a number. Repeatable from season to season and seed to seed.
No elbow on the mini hopper to impede seed flow. Less time spent shaking hoses because of seed stuck in the delivery hose.
All vac air is from the main hoppers. Cleaner air with less debris in meter housing.
Easier access to the meter with a 1.6 bu hopper. No need to remove the hopper from the unit to access the meter. All done from the side.
With new quick change doors, you can easily snap in the knocker wheel and bean flapper. They are no longer bolted in.
Here are some pictures of the new row unit