Quite often lately, when I shut off the engine I hear a gurgling sound at the rear of the engine. I hear it when sitting in the drivers seat. The truck has just shy of 260,000 miles on it. Just put in a new cummins thermostadt late last year. The truck had been overheating last summer when at stoplights. Any ideas, anyone ?

 

is it low on coolant?

 

Relax, its the heater core.

Check your coolant level...

 

My heater core only gurgles when the engine is running....rarely at that.

 

Burp it. Take off the radiator cap when cold, start it and shake it. Watch coolant level and top off with mix.

 

I'd say its the heater core too.. mine only did it for about a week or 2 after I replaced it. Like stated above, run it and leave the radiator cap off until the thermostat opens. It takes a while..

 

Try to have the nose of the truck pointed uphill when you bleed it. Having the top of the radiator higher up than the heater core will help to move trapped air toward the radiator where it can vent out.

 

I have been monitering the coolant level since it got hot last summer & it has been showing good on the overflow tank. Was wondering if the water pump was on it's way out or something like that.