This week we had a 2007 Mazda 3 needing an oil leak diagnosed and repaired.
We found the engine's rear crankshaft seal was leaking. Replacement of the seal would require the removal of the transmission for access to the leaking seal. After removing the transmission it was determined the clutch was worn and near the end of its life.
With some vehicles there is an inspection cover that can be removed to check the seal for leakage. If there is no removable inspection cover the leaked oil will collect at a drain hole and the transmission must be removed to confirm where the oil is leaking from.
Replacing the clutch at this time would be good value since 90% of the labor had already been done to access the crankshaft seal. The flywheel was resurfaced to prevent smooth clutch engagement without clutch chatter.
After the repair was completed the vehicle was test driven and to check that all work was performing correctly.