gOT A USED 1990 325 ic iT HAS AN OIL LEAK. my mechanic does not know if it is the valve cover gasket or the rear seal. He think it could be the VC gasket since the engine is slanted and the oil is running backward to the rear seal. Are the rear seals known to go?? Also, steering has loose feel when bumps are hit. Car was check and tie rods etc are fine. any thoughts.