Moroso 25030 Moroso GM LS Engine Oil Galley DiverterMoroso 25030 Moroso GM LS Engine Oil Galley Diverter GM LS Rear Oil Galley, Passage Plug, Also Called GM LS Dog Bone Or Barbell Fits GM Gen III & IV LS Engines 4. 8L 5. 3L 6. 0L 6. 2L (Including Vortec Truck Engines) Machined billet aluminum oil passage plug (AKA "barbell") for use with GM Gen III IV LS engines Replaces O. E. M. plastic plug that could allow oil to bypass filter when worn Secondary O ring added to prevent dirty oil from flowing to