Availability: 6 in stock
The vent panel here is the GM part, numbered 85557478. It is catalogued under Covers & Caps > Panels & Plates.
Covers that seal a fluid opening normally carry a single-use gasket or O-ring, and reusing the old one is the usual reason a leak comes back.
Confirm the number before you order, because a near match will bolt on and still be wrong. Send the VIN if the old marking has gone. Ships from our US warehouse in one to two business days, free over $59.