3.8 LITER. Oil tube o-ring. An item used to seal the fitting between the Oil Cooler and the Oil Cooler hose. Automatic Transmission Oil Cooler O-Ring. O-Ring used on the Engine Oil Cooler Line. pipe o -. Automatic Transmission O -. Engine Line Connector O -. Hose Assembly o -. Inlet o -. Outlet o -. Return o -. Included with: Cooler Line, Cooler pipe, Hose & Tube Assembly, Hose Assembly, Inlet Tube, Lower pressure Line, Oil Cooler, Outlet Tube, Return Tube, Tube Assembly, Upper pressure Line.