Modifying a divorce agreement can be done, but it may be more difficult than you might think if your divorce has already been finalized. Filing Your Modification.Complete the petition for modification and file it with the court, along with the filing fee. In Pennsylvania, while the law allows for modifications to divorce agreements, there are specific and limited reasons under which revisions may be made. Is a Divorce Modification Possible? Information providing an overview of Divorce Law in Pennsylvania from the Pennsylvania Legal Aid Network. To seek the modification of a divorce decree, petitions must be filed with the court where the divorce was finalized. In Pennsylvania, you don't need to hire a lawyer to file for a mutual consent divorce. The simplest way to change your divorce outcome is to file a motion to modify the divorce judgment. Postdecree petitions in Pennsylvania most often involve requests to change a Dissolution of Marriage, Annulment, Legal Separation, or Judgment of Paternity.