[alsimon96]

I have a 2009 Impala, V6 engine. The overflow tank has fluid at the correct level. My problem is this - with engine cold, I remove radiator cap and fluid down so I add a little. After a few days, same deal. It is my understanding that when the engine heats up, it will push fluid into the overflow tank and as it cools down, it will suck fluid back into the radiator thus keeping it full. Is it possible that my radiator cap won't let fluid come back in from the overflow tank?

 

[kingnutin]

Possible, but not likely. How much do you have to add? It's normal for it to drop a little.

 

[alsimon96]

Thanks for the reply. I dont have to add much. Perhaps half a cup. Temperatures have always been fine. I expected it to be full when I took the cap off and it alarmed me when it was down by even a half cup. Thanks again.

 

[kingnutin]

Ok, that's totally normal. The level will drop slightly as it cools, it doesn't necessarily pull from the reservoir as it does so, no cause for alarm. Just watch the reservoir level, as long as it stays up, you should be fine.