Not all ticket properties in the system would be synced to Salesforce. If you make changes to the following 7 properties, they will be updated in Salesforce immediately:
Due By time
Deleted or not
If you make changes to one of the above parameters, the entire ticket properties list gets synced to Salesforce. So if you wish to change a "sync not-supported parameter" (such as Source), be sure to change one of the above ones as well to reflect the changes immediately.