Leakage Points

Examine the following areas for oil leakage:

Underhood
- valve cover gaskets
- crankcase ventilation grommet
- head gaskets
- oil bypass filter and oil filter adapter
- oil filter adapter gasket
- oil level indicator tube (dipstick) connection
- oil pressure sensor

Under Engine-with Vehicle on Hoist
- oil pan gasket
- oil pan front and oil pan rear seals
- crankshaft front seal
- crankshaft rear oil seal
- side bolts

With Transmission and Flywheel Removed
NOTE: Air leakage in area around a crankshaft rear oil seal does not necessarily indicate a crankshaft rear oil seal leak. However, if no other cause can be found for oil leakage, assume that crankshaft rear oil seal is causing the oil leak.
- crankshaft rear oil seal
- crankshaft rear oil seal retainer
- pipe plugs at the end of oil passages

NOTE: Light foaming equally around valve cover bolts and crankshaft seals is not detrimental and no corrections are required.

Oil leaks at crimped seams in sheet metal parts and cracks in cast or stamped parts can be detected when pressurizing the crankcase.