Is it impossible to shrink the Trucated Log file?
Yes, following code always shrinks the Trucated Log File to minimum size possible.
1) Replace DatabaseName with your database name
2) Replace TransactionLogName to database log name
USE DatabaseName
GO
DBCC SHRINKFILE(TransactionLogName, 1)
BACKUP LOG DatabaseName WITH TRUNCATE_ONLY
DBCC SHRINKFILE(TransactionLogName, 1)
GO
Is is simple?