garggle sound from passanger dash?

[CodySanders]

ok so i have a strange gargle coming from the dash. it does it when it sits at idle intermittently more when it warms up and if i give it rpms it goes away. it will also do it on a down shift sometimes if i use gears to slow down. my heater has also decreased in heat as well. the sound apers to be getting worse. i wonder if anyone has had this happen and what it was. things done have been / replace all hoses with mr bobs and a new radiator t stat and a flush to see if it was trapped air bubbles. none of that but the flush was done to fix it just recent things done with the cooling system. i also have not noticed any fluid loss or leaks under or in the truck, and the oil is not contaminated either. thanks for the input

 

[Skydiver]

Next time your engine is completely up to operating temp. open your coolant recovery bottle while it is running. Do you see any air bubbles? Replace head gasket if yes.

 

[CodySanders]

no air bubbles at all and the level in the reservoir is exactly the same. i marked a line on it. any other thoughts? this is not a problem i have had since i got the truck. it just started doing this and it has not caused a problem yet but it is very annoying.

 

[CodySanders]

sorry i will move this post to the 12 valve forum. it is on my 98 12 valve not the 06. thanks

 

[Grizzly]

Since your heating has decreased, I would have a radiator shop clean and rod the heater core. Sounds like that may be doing the gargle

 

[LRutigliano]

ok so i have a strange gargle coming from the dash. it does it when it sits at idle intermittently more when it warms up and if i give it rpms it goes away. it will also do it on a down shift sometimes if i use gears to slow down. my heater has also decreased in heat as well. the sound apers to be getting worse. i wonder if anyone has had this happen and what it was. things done have been / replace all hoses with mr bobs and a new radiator t stat and a flush to see if it was trapped air bubbles. none of that but the flush was done to fix it just recent things done with the cooling system. i also have not noticed any fluid loss or leaks under or in the truck, and the oil is not contaminated either. thanks for the input

Did your "new" thermostat have jiggle pins on the flange surface (holes with a flattened pin that will let air and coolant flow the opposite way)??



If not, then you have air trapped in the heater core.



Our trucks don't have surge tanks, they have overflow tanks and the heater is the highest spot in the coolant loop. Without the jiggle pins in the thermostat, you may never get the trapped air out of the system...



ie- use a Cummins thermostat...