Coolant loss. No visible leaks. Head gasket?

Jacob broese

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Nov 8, 2017
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Hi. New member to the forum. I have a 2003 EB expedition with the 5.4. Having a coolant loss issue. I have been doing some research but have not been finding any helpful info. To start from the beginning, the truck runs great. Has 273,*** miles but has been taken care of so you can't even tell. I have been losing coolant for about a month. When the engine is running ijn park the coolant level in the reservoir will rise and eventually will blow out of the tank. I suspect this is where my coolant loss is coming from. I had this problem about 3 months ago and after trying to diagnose it, it all of sudden went away on it's own. Then it recently came back and I have been adding more water than coolant to keep it filled and prevent overheating. My problem is that we are approaching the cold season and I'm worried about it freezing up since I have been adding water to it. I can't exactly afford to add coolant to it every single day. Im averaging about a half gallon loss each day. Here is a list of things I have replaced recently as far as cooling related goes:

Water pump
Bypassed heater cores (front and rear, have hooked back up since it's getting cold)
Upper and lower intake gasket.

I have a set of head gaskets but having the time to install them is an issue for me at the moment.

So asking opinions on What else to look for. I'm kinda stumped on What else it could be. The pressure build up in the reservoir happens when the truck is warming up. Once the thermostat opens it seems to come and go at that point. I am having a slight coolant smell in the cab but it comes and goes. The floor board is dry so I'm ruling out a leak there. I can't tell if the smell is coming from the coolant seeping from the tank and coming thru the vents. My heat has been acting erratically as Well, heat comes and goes constantly. Also I have white smoke that comes from the exhaust that goes away after the truck warms up. Only happens when starting the truck up after it sits for a little bit. There is no water in the oil and as far as I can tell no oil in the water. Will a compression test tell me if my head gasket is Leaking? Maybe a leak in between the cylinders? Any help would be appreciated. Thanks in advance.

Big Brian

Full Access Members
Mar 27, 2017
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Farmington Hills Mi
sounds like a head gasket

while the engine is running take your hand and cup it around the exhaust at the tail pipe for a few seconds and smell your hand. If it smells sweet you are burning coolant (or you have been into the kids Halloween candy again)


That One Member
Supporting Member
Mar 30, 2017
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New York
Almost every vehicle has white smoke on startup, that’s condensation. Almost every vehicle has a hint of antifreeze smell under the hood whether it’s brand new or old. The caps don’t seal perfectly and you get a little smell from the heat cycles. But you shouldn’t get that strong coolant smell in your cab. if your heat is going in and out that head gasket may be your problem.
Last edited:


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Aug 13, 2020
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Dallas, TX
I Know this is an old thread , but hope this helps someone ,
i was having the same issues could not find a leak , did a compression test
leak test and nothing , so i was going to change out the radiator
and when i pulled off the top cover found my leak ,
a small crack in the top part of the radiator see photos , so i tried some stop leak it did not work .High temp RTV nope so off to the junkyard to get one , i can't afford $200 to replace it with a new one Hope this helps

03 Expedition IMG_20220805_195944.jpgIMG_20220805_200042.jpgIMG_20220805_200004.jpg

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