I have a 94 f150 4x4 5.0. Have have a leak some where I think, and I can't find it. I thought it might be a blown head gasket, but I have no symptoms of that. No antifreeze in the oil, no oil in the antifreeze, no white smoke out of the exhaust, no antifreeze smell out of the exhaust or the heater vents. truck runs great accept it gets a little hotter than it used to but it never overheats. The heat gauge does fluctuate and it never use to do that. The thermostat gasket was leaking and I replaced it. But I'm still losing some cool it somewhere. The coolant level in the radiator will drop even if the vehicle has been sitting for days. Not much but a little. I have checked all my hoses in connections the only thing that I can think is it might be leaking around a water pump somewhere. Where else should I look please help getting frustrated.

 

How old is your pressurized radiator cap?

 

Brand new

 

when you startup your truck in the morning and turn on the heater, does the cab fill with smoke? mine did that and I had to change the heater core. my radiator has a slight leak as well so I have to replace it. but I would clean the top of the engine as well as under neath the engine. get as much of the grease and grime off as possible, run the engine for a while, and look for any moisture. you can do the same thing if you have a oil leak to find the leak.

 

mine did/is doing the same thing ended up being a small hole in the radiator that only leaked when it was cold. patched the hole and it aint leaked in a good month or so.

 

yes look for a white-ish residue, like water stains all around the radiator. Up and down both sides, and especially along the bottom. I found a hairline crack in my mom's radiator that way, right below the hose nip

 

A pinhole...all it takes.

Thinking a flush will either kill you (present your leak origin), or make you stronger (all will be well again).

Use the Prestone heavy duty flush. Actually less corrosive to metal than the 10 minute flush, & devolves the Scale down to an easily passable silt.

 

Had a similar leak on my 96 5.0 Explorer. The t-stat housing being aluminum, had porosity in the neck for the bypass hose and would seep past the hose. If yours is aluminum, you might check both it and the radiator hose neck.

 

I'm kind of paranoid what are the chances that it could be a head gasket.

 

A history of multiple overheats, or one good "mother of all" overheats?

Any other of the usual symptoms?

No? Then I doubt it.

Take it to a radiator shop & have it pressure tested. There is also a chemical test that identifies combustion by-product's in the coolant. However, the older your coolant, the less reliable.