What does the letter following my model number mean? John Deere 40, 420 and 430 model tractors had many different variations. Each variation has a letter which is on the serial number tag after the model number. These are the letters for each model:

 

 

  • Crawler designation is “C”
  • Hi-Crop designation is “H”
  • Special Utility designation is an “I”
  • Orchard designation is an “O”
  • Row-Crop Standard is “RC”
  • Standard designation is “S”
  • Tricycle designation is “T”
  • Utility designation is a “U”
  • Special designation is “V”
  • Row-Crop Utility designation is “W”

For example, if your serial number tag has “420 –   W,” then your tractor is a 420 Row-Crop Utility.