I topped off my coolant a few weeks ago because it was slightly below the cold fill line. I filled it to the top mark of the cold fill line. Well today I looked at it and its starting to disappear again. Its almost a quarter of an inch below the top fill mark.

Anyone else seeing this with there 5.0s?

 

How many miles on your car? I added some coolant to mine at about 9k mi. Now I'm at 24k mi and have'nt added any since.

 

I'm at 17k right now. Did yours go down at all?

 

At 9k mi the coolant was at the low mark. I topped it off and It's been ok since then. Maybe you can top it off ,then go out and run it til it gets hot . Then check for leeks.

 

As long as your in the safe area, you should be fine.

 

I noticed when my car was brand spanking new that my coolant level was at the very bottom of cold (come on Ford, couldn't have given us $.50 more coolant could ya...cheap asses). Mine is still on that mark, but I did hear on an occasion after I started it up and moving an obvious what I would call an air bubble in the heater core (high point) for a split second. I'm going to keep my eyes and ears open for any other coolant loss or consistent gurgling from the dash upon startup.

 

Mine was like that as well then it went down. I thought the coolant system was a closed system so I'm confused as to why it's losing coolant.