I have a 1995 cherokee 4x4 , 4.0 auotmatic with 129,000 miles. the JEEP is strong. Replaced the radiator, water pump and t-stat because of over heating. the radiator was leaking from the plastic ends. When I remove the radiator cap while the engine is running air bubbles appear. I keep losing coolant with no evidence of where it is going. the coolant takes on a brownish color which I presume is exhaust contaminates. Engine oil is fine and very clean. Is it possible I have a gasket leak at an exhaust/water junction. I read on another site that this was impossible with the 4.0. I am handy enough to attempt this , just need a little guidance.