Oracle audit table AUD $ excessive data

1) Only appropriate privileged user can do delete operation on SYS. AUD $ table. The user must have either of the following privileges.
-SYS user.
-Delete any table system privilege. (If O7_DICTIONARY_ACCESSIBILITY = TRUE)
-A user to whom SYS has granted the object privilege DELETE on SYS. AUD $ table.

2) Before deleting any rows you may want to archive the table. you can achive this by creating a table from SYS. AUD $ and export that. don't export SYS. AUD $ directly.
SQL> CREATE TABLE AUDIT_RECORD TABLESPACE users as select * from SYS. AUD $;
Now export the table,
SQL> host exp tables = AUDIT_RECORD file = audit_record.dmp

3) To delete all records from audit trail table SYS. AUD $ issue,
SQL> DELETE FROM SYS. AUD $;

To delete all records of particle audited table from the audit trail issue,
SQL> DELETE FROM sys. aud $ WHERE obj $ name = '& table_nmae ';

But deleting in this way will not reduce size on the system tablespace or aud $ table. In order to reduce size follow section 4.

4) Truncate audit table to reduce size.
SQL> CONN/as sysdba
SQL> TRUNCATE TABLE SYS. AUD $