The are almost identical, Carlton simply changed the way they "number" their machines. The 2400-4 will have a single speed drive ( the 7015 generally will have a two speed), the 2400-4 will have a single hydraulic drive motor that drives a chain and axle assembly "powering" the wheels (the 7015 will have two hydraulic motors-one at each wheel hub, "powering" the wheel directly). Sometimes the operators control "station" is a bit different depending on how old the 2400-4 is. Also the 7015 will have a Kohler 27 hp engine whereas the 2400-4 had a Kohler or Onan 24 hp engine. Cutting performance is basically the same as is parts availability.
