Q: Gray oil under oil cap

asked by on June 27, 2017

Vehicle shows Gray Somewhat Foamy Oil under the Oil Cap. It's not milky nor Shooting massive smoke out the tailpipe Either. The Dipstick Shows Clean oil on it. This is after running the car through the gears ext ext. Car dosent overheat. Fluid levels of oil or coolant dosent decrease Either. I'm not short tripping the car. I've actually left it running after trips for about 20 mins to check and see.

My car has 92500 miles.
My car has an automatic transmission.

There are quite a few labs (just do Internet search) that perform passenger car engine oil analyses and such a service is economical as it is done through the mail. Visual observation, in the circumstances you are describing, will not tell you much; instead, obtaining a lab report will tell you exactly what is in the oil. When I say, "your circumstances", you are reporting no change in coolant level; consequently, the most likely explanation for the gray color observed under the cap is condensation. If you desire a further, on site, inspection please feel free to request that using YourMechanic’s service request link. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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