L3
1. Disconnect the negative battery cable.
2. Remove the plug hole plate.
3. Remove the high-tension lead. (See HIGH-TENSION LEAD REMOVAL/INSTALLATION.)
4. Remove the oil control valve (OCV) connector.
5. Remove the ventilation hose.
6. Remove the cylinder head cover. (See Cylinder Head Cover Installation Note.)
7. Remove in the order indicated in the table.
8. Install in the reverse order of removal.


Oil control valve (ocv) inspectionMazda 6 Service Manual: Contact Authorized Mazda Dealer and Have Vehicle Inspected
If any of the following warning lights or the indicator light turns on/flashes,
the system may have a malfunction. Contact an Authorized Mazda Dealer to have your
vehicle inspected.
...
Mazda 6 Service Manual: Oil seal (differential) replacement
1. On level ground, jack up the vehicle and support it evenly on safety
stands.
2. Drain the oil from the transaxle.
3. Remove the front wheels and splash shields.
4. Separate the drive shaft and joint shaft from the transaxle. (See DRIVE
SHAFT REMOVAL/INSTALLATION.) (See JOINT SHAFT REMOVAL/ ...