I have a 09 1500 Hemi that runs great and is not over heating, but I am losing coolant somewhere, but am at a loss. There always seems to be some in the radiator, but the reservoir bottle (even if filled up) is empty after driving it around a little bit. I am not the first owner and know the water pump has been replaced in the past. I am not sure where the leak is. There is never anything on the ground and I don't seem to see anything smoking, if it's burning up inside. Anyone have any thoughts of advice of where to start?

 

Have the cooling system pressure tested to 16 psi for about 5 minutes and the cause will usually reveal itself.

 

Re trace your steps and I would start with the hoses don't forget the hoses going to the firewall to the heater core. Look also at the radiator especially on the sides from top to bottom for traces of coolant that cooked up and left residue. My girlfriend's Toyota Corolla was doing the same, I found the source it was a leak in the top driver's side of the radiator from where she had an accident several months ago. The problem never revealed itself as it was hard to see where it was and how I knew is she said the car was running hot.

 

Onto the ground, into the crankcase, or out the exhaust are the only options as to where it could be going. A shop can check your oil & coolant to see if they are contaminated (exhaust gas in the coolant or cooling in the oil).
Mike Sal

 

I second the recommendation for a pressure test. Don't forget to check the passenger front floor inside the cab in case the leak is from the heater core.

-Rod

 

Pressure test is a good idea don't get me wrong, but look again sometimes it can be see by the eye and you cann find evidence of it. Would hate to pay out for a pressure test only to find it was actually in an area where I overlooked and was obvious. That being said, that's why I would look again at it thoroughly then do the pressure test.

 

WHAT!?! Doesn't everyone have their own pressure test kit?

I sometimes forget that not everyone considers a car issue an excuse to buy another tool.

-Rod

 

Wait, what? What are you saying there? Surely you aren't trying to convince me that its not.........

 

Thank you for everyone's responses! This is what I did today to test and am still at a loss.

- Pressure tested the cooling system (connected to the radiator)
-- I did the tests with the engine off and to 16 PSI
-- I did another test with the engine running (rev'd the engine to 2500RPM for a few minutes)

RESULTS
- No apparent leaks
- It BARELY lost pressure after 5-10 minutes, but DID lose some pressure

THINGS I CHECKED
- I do not see any liquid in the exhaust
- The oil does not look like chocolate milk
- The bottom of the oil cap doesn't appear to have any build up on it
- Transmission fluid looks clean/clear
- Hoses aren't bubbled around the clamps
- Radiator fluid doesn't look carbinated

 

Then the next step may be to carefully inspect the reservoir bottle. With the pressure test the reservoir bottle would be about the only thing not in the loop. And in your original post you mentioned the radiator is almost always full but the reservoir bottle level is dropping.

-Rod