Engine Coolant

[Bliky]

So the other day I was looking at my engine bay and noticed the coolant in the coolant reservoir was about an inch (maybe a half an inch) below the MIN mark. Not sure why, or what's eating the coolant but I really want to make sure it's full and won't cause any harm before my road trip this weekend.

Did the fact that it had a really low level of coolant mean something like it's leaking? The fact that it possibly has been like that for a while... Could it have caused any damage?

I need to refill it... Do I absolutely need to buy the Motocraft orange stuff the manual says or will Prestone 50/50 work? Does it have to be orange or will any color do?

[Sponsor]

[nseah]

It happened to me too, almost the exact same situation. Been using it with that level for over a year, no problem. I took it into Ford to look at, they topped up the fluid free of charge (shouldn't be running this low this quick). It's remained at the MAX level since then. My guess is initially they didn't put enough fluid in maybe.

[PratoN]

I checked mine this weekend and it was like 1 inch lower than the MIN line too! As far as I know, it's always been relatively low / at the minimum, but I don't think I had ever seen it this low.

[Bliky]

Originally Posted by nseah

It happened to me too, almost the exact same situation. Been using it with that level for over a year, no problem. I took it into Ford to look at, they topped up the fluid free of charge (shouldn't be running this low this quick). It's remained at the MAX level since then. My guess is initially they didn't put enough fluid in maybe.

Originally Posted by PratoN

I checked mine this weekend and it was like 1 inch lower than the MIN line too! As far as I know, it's always been relatively low / at the minimum, but I don't think I had ever seen it this low.

Interesting. I mentioned it to a mechanic buddy of mine who works on Porsche's and his reaction was "Every new car I see now a days just seems to eat coolant. It isn't leaking, it just is disappearing." I wonder where it's all going.

I guess by the reaction i'm getting I really shouldn't worry too much about it. At least for now.

[RedComet]

Has it been cold lately in your neck of the woods? On the coldest days, I've noticed that my coolant level drops due to temperature, similar to how air becomes denser at cold temps causing false positives on your TPMS. Similar effect.

[slybarman]

It's a closed system - it can't just disappear.

[suss6052]

Originally Posted by slybarman

It's a closed system - it can't just disappear.

The pressure cap will vent if the pressure exceeds the rating of the cap which is usually around 16-18 psig, so it's not 100% sealed in that case, although generally it should remain below this threshold, and if it was leaking from the cap you'd see some evidence around the reservoir.

[Vernl]

Originally Posted by Bliky

So the other day I was looking at my engine bay and noticed the coolant in the coolant reservoir was about an inch (maybe a half an inch) below the MIN mark. Not sure why, or what's eating the coolant but I really want to make sure it's full and won't cause any harm before my road trip this weekend.

Did the fact that it had a really low level of coolant mean something like it's leaking? The fact that it possibly has been like that for a while... Could it have caused any damage?

I need to refill it... Do I absolutely need to buy the Motocraft orange stuff the manual says or will Prestone 50/50 work? Does it have to be orange or will any color do?

Go buy a ltr bottle of non ionized water at the supermarket and top it off with that...you will only be adding a few ounces and you dont have to worry about affecting the strength of the coolant...I did the same thing over a year ago and still have 80% of the water sitting on a shelf in the garage

[TboneZX3]

Originally Posted by RedComet

Has it been cold lately in your neck of the woods? On the coldest days, I've noticed that my coolant level drops due to temperature, similar to how air becomes denser at cold temps causing false positives on your TPMS. Similar effect.

There is a similar effect. However, since air pressure should be checked when tires are cold, I wouldn't consider low tire pressure during cold weather a "false positive".

Originally Posted by Vernl

Go buy a ltr bottle of non ionized water at the supermarket and top it off with that...you will only be adding a few ounces and you dont have to worry about affecting the strength of the coolant...I did the same thing over a year ago and still have 80% of the water sitting on a shelf in the garage

This is good advice. Use distilled water.

[bile0026]

Don't mix coolants. At least don't mix colors. There are usually different additives in the coolants that could react negatively if mixed. I would just top it off with a bit of water as Vernl suggested. Water will expand when hot and contract when cold just like air so if it has been cold I would not be surprised if the level is a bit low.

I'm assuming it is just below the MIN mark when the engine is cold? If it rises above the MIN when the engine is hot I wouldn't worry about it as it is just some expansion and contraction. The system was filled in a warm factory and is now sitting out in the cold and has contracted a bit. If you are worried just add a few oz's of water.