'90 525 oil leak

[HPeterCoke@xxxxxxx]

My wife's 1990 525i has developed an oil leak.  It appears to leak at the back
of the oil pan a minute after the car is turned off.  I had it up on a lift
and ran the motor but it would not leak until after the motor was turned off.
Is there some method where by the crank case can become pressurized once the
motor has shut down.  It does not appear to continue to leak but may put out a
tablespoon of oil before stopping.  I assume that the cross member can be
dropped to remove the oil pan to replace the gasket.  Is this just a failed
gasket or is something else hapening?
Thanks,
Peter Coke

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