Leaking Coolant, but not from radiator???

could be head gasket leaking if there are no obvious leaks from hoses,gaskets,radiator etc

Can be several things. Bad Radiator, Bad hoses on radiator, or nearby water pump is leaking.

They make a Radiator pressure tester which will put pressure in the system so you can see where the leak is coming from.

REPLACE THE THERMOSTAT AND RADIATOR PRESSURE CAP.IF COOLANT LOW, ADD MORE COOLANT THROUGH COOLANT OVERFLOW UNTIL COOLANT LEVEL IN THE COOLANT OVERFLOW STAY AT FULL COLD MARK.REASON POUR COOLANT THROUGH COOLANT OVERFLOW MOST GM CARS DONT HAVE RADIATOR CAP.WHEN YOU GET COOLANT LEVEL OKAY, CRANK CAR LET IT IDLE UNTIL ENGINE GET HOT BUILD UP PRESSURE THEN TURN OFF CAR.CHECK FOR COOLANTS LEAKS AT THE RADIATOR HOSES,CHECK FOR LEAKS AT THE RADIATOR, CHECK FOR LEAKS AT WATER PUMP WEEP HOLE IF YOU SEE COOLANT LEAKING FROM WEEP HOLE REPLACE WATER PUMP. IF CAR OVERHEATING WHILE IDLING YOUR COOLING FANS NOT WORKING CHECK COOLING FANS FUSE AND RELAYS.IF FUSE AND RELAYS OKAY THE ENGINECOOLANT TEMPERATURE SENSOR BAD.

it could be one of the hoses leaking. with your car running look under the front and see where it is coming from. The top/bottom hose coming off the radiator or MAYBE from the water pump

bad thermostat and coolant maybe low. when a engine gets to hot at certain boiling point it evaporates

Replace the bad radiator hose first.  Second- get you special formulated anti-freeze dye from the auto store and pour it into the radiator.  Third- make sure you got all the air pockets out of your system, cause the coolant system won't work with air pockets in it.  Fourth- Check for leaks by looking for the colored dye.  If it's not the radiator hose, then could possibly be a pin hole in your radiator.  Would suggest replacing all the radiator hoses at the same time while you got the coolant system disconnected, cause you don't want to have to come back and replace another hose in a few months.

Just because it was not hot to the touch, does not mean it is not a coolant loss problem----if the coolant is so low, there may not be enough to make the radiator hot (though usually the steam in the system will).
...a stuck thermostat can also let the engine overheat while the radiator remains cool (the fluid only circulates within the engine and is stopped from getting to the radiator.
...likewise a hose could have burst below and let the coolant out, over heating the engine, and the steam going out the ruptured/popped off hose; would look underneath..
...when cool, check the level in the radiator (likely empty),
...and less than a mile away, may not have ever heated the radiator, though usually only a mile to heat up the coolant
...of course there is always sabotage
...and water pump failure, (so no water circulated) causing overheating and no radiator heat, and possibly enough pressure to blow off a hose, but usually the radiator cap relief spring would allow pressure to escape (and that steam would heat up the radiator on the way---but if only steam in the radiator, it would cool off quickly after venting, because no more water in the radiator to hold the heat. all depending on climate,temp and further details , symptoms..
hope helps..

Hi..my name is Keith..and if its leaking up front in the middle..its your water pump..it has a weep hole in the bottom of it..and when the bushing goes bad..the coolant comes out the hole in the bottom of the water pump..but it could be other things..but thats the most likely suspect..if not please write me back and i will help you further

i think its going to be the head gasket duto the way its leaking coolant. one of the water jackets maybe i would have it checked to be sure but it sounds like head gasket

1 Inspect Oil Pan Gasket - Performance Ruptured, cracked or leaking radiator hose. 2 Inspect Hose (Bypass) Ruptured, cracked or leaking bypass hose. 3 Inspect Hose (Heater) Ruptured, cracked or leaking heater hose. 4 Inspect Radiator Cap Worn or damaged radiator cap 5 Inspect Heater Core Heater core may be leaking antifreeze/coolant into the vehicle`s floor area. 6 Inspect Heater Control Valve Leaking or defective heater control valve. 7 Inspect Radiator Drain Plug Loose, damaged, or faulty radiator drain plug. 8 Inspect Radiator Rusted, corroded, or damaged radiator may be leaking antifreeze/coolant 9 Inspect Water Pump Damaged, worn or leaking water pump. 10 Inspect Cooling System Mix Coolant level low or flow is restricted. 11 Inspect Head Gasket - Performance Blown head gasket 12 Inspect Hood Brace Leaking, worn, or damaged intake manifold gasket 13 Inspect Freeze Plug Freeze plugs are cracked or leaking.