The cause of an engine oil leak is a damaged
Engine Oil Cooler hose/pipe adapter gasket or a previous oil leak servicing of the engine oil cooler hose/pipe adapter gasket that involved failing to remove the temporary steel sealing device. Another reason may be the casting porosity at the engine oil cooler hose/pipe adapter bolt holes of the engine, and the engine oil cooler hose/pipe adapter bolts are not torqued to the proper specification.