f you want to export a file that contains zip codes, but remove the +4 at the end of them, there are only 2 ways to do this:
1) Create an Export and select your desired Fields along with Zip code field. Click on Fixed Width File on the left to bring up theLength box under the fields. Click into the Zip code field and set the limit of the export field to be 5 characters long to leave off any +4. You have to enter in a character length for the other selected fields as well, otherwise they won’t export. Choose a big number such as 20 to try to get all the information of that field. There is a chance you may lose some information this way though depending on the length of the information contained in the field.
2) Another way to ensure no information is lost is that you could edit the zip code column after the export is dowloaded. The following link will show you how to truncate the values in a column: