Exposing the Truth Oil Contamination in Coolant Reservoirs

Coolant can react to oil and make it sludge, which isn't good, and coolant in your lubrication system would be bad. So the next step is to ... Damaged head gasket · Faulty Oil/Coolant Heat Exchanger · Cracks in the cylinder head · Cracks in the engine block. I noticed oil in the coolant. No foam on the cap and no foam on the oil cap either. Checked everything and doesnt seem like a head gasket thats blown. Replace oil cooler. Fill cooling system w/ fresh water. Add a small(!) amount of detergent to coolant tank, run vehicle for a short bit. Drain. Oil in coolant is a leaking oil cooler. Coolant in the oil can be many many things, with the head gasket being low on the list. Coolant in the cylinder is a ... Engine oil in coolant! ... Yikes. Not a common issue. My suspicion would be head gasket. Did you buy this car from a dealer? ... That's bad! Most likely thing is the transmission cooler leaking internally in the radiator as you have already mentioned. The second most likely thing from ... If you have oil in the coolant jug then you have a blown head gasket. Depending on if it's overheating your car is going to die. The problem, in general, is that there is a leak between the lubrication system and the cooling system. There are only few obvious where this can happen. E60 Discussion - Oil in coolant reservoir - So after taking my BMW to a local INDY he replaced the oil cooler and oil filter housing did 3 ...