On a Windchill 9.x System use the jconsole command from a windchill shell and connect to one of the methodservers. Then mbeans tab and com.ptc / Monitors / CacheVaultSynchronizer / Operations and you will find the sync interval there initially set to three hours - you can reduce it to a min of 1 hour.
On a Windchill 10.x System run Jconsole with the command windchill wt.util.jmx.SMJconsole Go to mbeans tab and navigate to com.ptc / MethodServers / MethodServer / Monitors / CacheVaultSynchronizer / Operations.
Rgds
Gary