i have a 1999 grand am gt. I checked my resovoir tank today to discover oil in my coolant. My oil is fine, there is no water. What do i have to do..?

You are probably going to need to replace your radiator, it sounds like there is an internal leak causing the fluids to mix. What you are seeing in your resevoir is actually transmission fluid, so when you get the radiator replaced, it would be highly suggested that you get the transmission fluid changed as well. Good luck.

I just got back from a garage... it is 110% gauranteed motor oil. but there wasn't as much as I thought... there was only 2 or 3 tea spoons.
they removed the resovoir tank and emptied it.. and the oil was laying on top of the coolant. They are totally baffled. the only thing they could come up with is... did I put oil in the resovoir tank instead of the oil? The answer is NO!
Although I had Wal Mart super center change my oil a few months ago.. maybe they screwed up. The garage I went to today said there is no possible way for motor oil to leak inside of the coolant system...


You are probably going to need to replace your radiator, it sounds like there is an internal leak causing the fluids to mix. What you are seeing in your resevoir is actually transmission fluid, so when you get the radiator replaced, it would be highly suggested that you get the transmission fluid changed as well. Good luck.

Do you run dexcool in your cooling system? The brown scum that develops on top of the coolant after exposure to air looks like motor oil, it feels oily and will look like oil. So make sure to keep an eye on it but I will bet that you will see this again.

i believe the brown scum is brine, which is caused by the sodium in the DEX and the combination of heat and pressure, just my :2cents: