Sierra 18-3862 Head Gasket The Sierra 18-3862 Head Gasket is interchangeable with the following: GLM 35860, Mallory 9-63853, Mercury 27-41246-1, 27-41247T01, 27-41246, 27-41247, 27-96543, 27-41262. Each Sierra product meets or exceeds the original equipment part it replaces. Sierra Head Gasket Meets or exceeds the original equipment quality Sierra part number: 18-3862 Interchangeable with the following: GLM 35860, Mallory 9-63853, Mercury 27-41246-1, 27-41247T01, 27-41246, 27-41247, 27-96543, 27-41262