Some points to be aware:
2D fields, not same by binary output and netcdf (high efficiency) output, one point value missing, might be the polar point. Therefore, *.bin control and *.nc sensitive is not under the same structure.
2D fields work fine under v1.9 of grads. However, 3D fields might meet some trouble. Try to use the “standard” attribution, dimention to tackle this problem. An example from NCEP-DOE dataset:
float level(level) ; level:units = “millibar” ; level:long_name = “Level” ; level:positive = “down” ; level:GRIB_id = 100s ; level:GRIB_name = “hPa” ; level:actual_range = 1000.f, 10.f ; level:axis = “Z” ;