All-
Noob to the forum......I've searched and found similar threads but nothing that has answered my question - I'm hoping someone will be able to!

I have a 1997 5.9 (gas) 2500......been smelling antifreeze for a while (both cold and after being driven). The radiator was only low enough once this past winter to alert me on my temp gauge. Otherwise, always full when I check it. The overflow bottle, however, is normally empty (despite adding to the fill line).

I've been constantly looking for leaks on the ground, around clamps and hoses, but never see even a drop. I hadthe system pressure tested and told no leaks were found. I do not see any milkyness on the dip stick nor have I seen/felt the passenger side carpet being wet. I do, however, smell some antifreeze when the heater is on but have never experienced steaming of the windows.

Sorry for the lengthy post......any ideas?? Thanks!

 

filling your overflow bottle does nothing. the coolant does not go back into the radiator.

YOu need to take your radiator cap off and fill that.

I think your problem is your heater core. If you put on defrost, does your windshield get a bit of a film on it at full heat?

That is your heater core if you smell it in cab.

I thought I had a leaky core on my 1996 because of the smell. Ends up the PO replaced it and the box it was in was not cleaned out of all remaining coolant. So it would give a syrup smell.

 

I had the same problem. Unexplained coolant loss. No apparent leaks, just disappearing coolant.... until... finally, I started seeing coolant dripping. Was the freeze plug behind the drivers side motor mount. Fixed that yesterday, see what happens now.

 

Sounds like my leak but mine appears to be the timing cover or waterpump gasket. Sounds like you have several places to check.

 

noticed my 97 had a bit of a sweet smell to it..found out it was the waterpump..very slow leak, not enough to register on temp guage and only pushed out after it came up to temp..

 

Thanks for the suggestions! .....I'll take a closer look at the water pump and freeze plug areas. Not so sure it's the heater core......ran the defrost/heat last night (though not at full blast) and didn't notice a film. Also, hadn't observed any wetness on floor by passenger.