I have a 2000 Durango 5.2 with the 318ci engine, 2wd. About a week ago it overheated, badly.. I was driving down the interstate and everything was fine. 2 minutes later the alarm is going off and i look at the temp gauge and it is all the way in the red. I added some antifreeze after it cooled to get back home. Checked it all out and the tube for the overflow reserve was laying on the belt and it wore a hole in it. Replaced that tube and topped the antifreeze off. Then the temp gauge wouldn't get to 210. It got to about 190 or so and just stays there. Heater blasts cool air unless I have my foot on the gas and it starts to blow warm. I was told it sounded like the thermostat was stuck open so I changed it out, topped with AF again. Still same issue. What could keep my engine from running to normal temperature? I do not see leaks or anything while running, idling or after running.

 

it sounds to me like you have air in the system and needs to be worked out, im not sure of the burping procedure on the 5.2/5.9l engines, but that is what you need to do, the system MAY burp itself over a couple of cycles if you are lucky.

also 190 is the stock thermostat temperature, so that is approximately where the temperature SHOULD be, maybe slightly higher.

amblin im moving your post to anew thread

 

I have tried starting it cool with the rad cap off and letting it run with heater set to defrost and wide open while watching it and adding more 50/50 every time the level drops, but it only blows out cool air(almost the temp of outside) I have also tried revving it, holding it at around 2.5 rpms(which is the only time warm air comes out of the heater)

 

The heater core might be plugged up or restricted. The same thing would happen to mine when it was on it's way out. Let it warm up and put your hand on the inlet hose of the heater core (beware, it's going to be pretty warm) and put your hand on the outlet hose of the heater core and note the temperature difference. My guess is the inlet will be hot and the outlet will be fairly cool and that will indicate a plugged up heater core.

 

I'm just getting started with working on anything, this is the first vehicle I've had that was paid for, so forgive my newbie questions. The inlet and outlet are located at the back behind the engine coming out of the dash? I tried to look up the location or pictures online but I can't really tell. Up until this the most I have done to a vehicle besides basic maintenance was change thermostats and replace stereos.

 

you are correct there will be two hoses going through the firewall on the passenger side where the heater core is located, you should be able to follow them from the water pump area (near the front of the engine)

 

Okay, coming from the firewall, the bigger pipe is cold, almost like its air conditioner cold, and the smaller pipe isn't either hot or cold. In the front under the radiator hose the bigger pipe is still AC cold and the other is slightly warm. In the very front behind the grill of the hood, the top pipe is warm and the bottom is neither warm nor cold.

 

I have pictures, but I don't have anywhere to upload them to show everyone.

 

You could sign up for Photo bucket and put them there... its free

 

Thanks Old_School. Cold is blue, warm is red, and neither is gray.