2010 explorer coolant leak

[muneeb]

I have bought 2010 explorer EB with 171,x.. Kilos on it. Ever since i bought, i am noticing that the coolant in reservoir is loosing its level below "full cold" when the car is cold. I refill it up to "Full cold" and car is cold and after one week i notice same that coolant in reservoir is much below "full cold" level. in last 16 days, i had added almost 800 ml to reservoir to maintain its level. My question is, where can i doubt of leaking? as a clue (maybe), when i park my car after a trip, i notice a "tik tik" sound of some liquid drop on the rear of the car behind driver side. sounds like a drop of liquid is hitting the muffler or the silencer pipe. Any idea to this problem? i am always in tension and avoiding long trips if there is leakage in cooling system.
thanks

 

[Tech By Trade]

4.0l? Either the thermostat housing, or the rad tank.

 

[Flag Gibby]

Not necessarily if there is liquid dripping in the rear where the rear HVAC stuff is. The coolant fittings on the rear heater core have been known to develop leaks sometimes. If he has front and rear heating/cooling then that is a possibility.

 

[Many3rdgens]

Also the water pump can leak for a while before leaking enough to start dripping. Out of all of my Explorer and Mountaineer 4.0 engines, our 2010 is the only one that has needed a new water pump due to leaking and it took me a while to figure that out. I also recommend most people to get rid of that silly 20 pound radiator cap Ford stuck on the fourth gens and run a 16 pounder. Even in 100+ degree towing I have not noticed a difference in engine temps on OBD2 since switching, other than a bit more action in the overflow and about 4psi less to cause leaks. The 3rd gens run fine with 16 pounds and the same engine.