Coolant has oil in it. The fluid in the radiator is a brown color . What to do????

Most common cause would be a blown head gasket or (similar failure) - in which case the oil on top of the coolant would be brown-ish in color.

Or, less commonly, a failed transmission cooler (built in to the bottom of the radiator), in which case the oil on top of the coolant would be pink or red-ish in color.

More details offered in your question, such as year, make, model, and mileage could possibly yield a more comprehensive answer.

check levil if levil what color is fluid brown or red take pan off look inside for metal and brown dust more then 1/8" bad possibly filter stopped

Flush coolant system again. Do you have a brown sludge in the oil. Do this get Preston coolant flush, drain radiator drain coolant tank, fill radiator with water, add the Preston run vehicle for about 15 min remove lower radiator hose from radiator. This will allow all residue to be removed from engine. Replace radiator hose. Fill radiator with appropriate amount of coolant. Disconnect tank from system and let water run through tank until it is clear. Reconnect tank and you should be good. Unless you have oil and coolant mixed which means a blown head gasket or cracked block

OK, lets figure out what's happening here. You are seeing "oil" in the radiator and coolant. Chances are it is not engine oil. The inly way engine oil can get into a radiator would be if a head gasket was blown. Even then, oil at those locations is not under as much pressure as the coolant is, so when a head gasket blows, what usually happens id that the coolant ends up in the motor oil and oil pan. Verify this by looking at the dipstick to see if it is extremely full. The oil could look like choclate milk. Also, open the oil filler cap and look for signs of chocolate brown goop. I'm betting you won't find that. This is good, but also bad. What you probably have in you coolant is transmission fluid. The transmission oil is circulated through a cooler located inside the radiator. If this cracks or breaks the transmission oil can leak into the coolant. However, at different times the transmission oil and the coolant are at odd with one another pressure-wise. This means that if you have transmission oil in the coolant, you probably have coolant in the transmission oil. This is very very bad, You will need to have the transmission serviced and possible overhauled to repair the damage. You will also need to flush the trans oil from the coolant system. This will require you to replace the radiator, ALL HOSES as well. Coolant hoses do not play well with transmission fluid . The inside of the hose sort of melts and gets real soft and gooey. Changing the hoses and radiator and flushing the motor should work once the transmissionhas been serviced.

Hello and welcome to FixYa!

Does it have a leak? If you are referring to the fluid that runs on the bottom of the radiator then it will be the radiator coolant.

The coolant color may vary. It can be green or brown that sometimes reddish in color.

Hope this helps and thank you for using FixYa! Have a good one!

First you need to identify what's leaking? What color is fluid? Green, Red, Brown? and where under car is fluid leaking from center, front rt, etc... Another option is check ALL fluid levels - coolant, oil, power steering, transmission.

If it's brown like a chocolate milkshake, then there is coolant in the oil. Otherwise it's likely dirty and needs to be changed. Hope this helps.

A flush and a thermostat is never a bad idea, but it sound like your radiator cap is worn out, not holding pressure, replace it, should have a 16 lbs rating radiator cap.

Hi. apparently the mechanic did not rinse the contents out completely after the flushing was administered. During the flushing of a radiator, there may be a good amount of debris that will build up, due to the flushing compounds effect on the crude inside the radiator. This is why there should be a rinsing stage to clean out all that is removed, via the flushing procedure. If the rinse is not done correctly, some of the contaminates will be left behind to mix in with the new radiator fluid. The rust/debris will mix contaminate the new fluid that is poured in, thus, causing the brown color you have noticed.

Most radiator fluids will be green, or orange in color, but never brown or greenish brown. This greenish brown will indicate that there is some rust deposited that were not rinsed out properly, after the flushing of the radiator. I would return the vehicle to the mechanic to request a re-flush of the radiator. They should do it for free.


NOTE_ A more serious issue will be a damaged oil cooler. this will cause the same symptoms within the color of the fluid, if your vehicle is equipped with this device. Once the oil cooler has ruptured, it will cause the engine oil to be transfer into the radiator, thus, changing the color of the fluid.

Have you had any Problems with the Motor???? If not, You just need a Radiator Flush and Fill. You really need one anyway to find out if there is a Problem that you cannot see Otherwise.