Q: Brown sludge in my coolant reservoir

asked by on February 17, 2017

As i was driving i noticed the low oil light on. I knew of an oil change i needed, which was soon to be done so assumed that was the issue. Then minutes later a little smoke was coming from the top right side out of the hood. I stopped and brown sludge was overflowing my coolant reservoir, causing the steam. I assume oil had leaked in the reservoir. No check engine light on, no overheating. Car was running fine, haven't started it since. Could this be a broken oil cooler or hoses? What should be checked and done?

My car has 204800 miles.
My car has an automatic transmission.

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Hello, and thank you for writing in. Oil is mixing in to the coolant, likely through a blown head gasket that is allowing oil to leak out and get into the cooling system. There are other reasons this can occur and they include a cracked head, and get more complex from there. With that being said, both checking for a cracked head and replacing the head gasket can be lengthy processes. You may be in a position where the best bet is a professional inspection, as they have the tools they need to diagnose the issue faster. However you can replace the head gasket at home if you feel you comfortable doing so, as well as run some basic compression tests. For more diagnostic help, contact our service department to schedule an appointment.

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