Tutorial author: FunGt
The cargrp.dat file controls which vehicles the SA ped groups will drive. Before following this tutorial I recommend to download this cargrp.dat (more readable version).
What does the lines mean?
sanchez, walton, rancher, journey, tractor, wayfarer, freeway, linerun, petro
In this line there are all the vehicles driven by the farmers. If you add the name of another vehicle on this line, the farmers will drive that vehicle too. The name of the vehicle can be written anywhere, remember to separate the vehicles with a comma.