I've been noticing lately, since I only drive my truck twice a week. I hear water slushing around under the passenger side of the dash. Its getting louder each time it its filling up more. Last Night I noticed my heat sucked. at highway speeds the heated seat warm me up more then the temp coming out of the vent. I think they are related.

So does anyone have any idea what I have going on here?

Thanks
Rick

 

check your coolant level.
I bet your heater condencer is cracked and is leaking into the hvac inside the cab.

I just replaced mine. Its not hard but takes a while and you have to disconnect the a/c lines.

 

The heater core can make a sloshing sound even if its ok.
Id check for the symptoms of coolant smell in the truck and a haze on the inside of your windshield with the defrost on.
To replace a heater core is a lot of labor so if you do you may as well do the AC at the same time.

 

Whats the chances of the drain being clogged up? Not loosing coolant, but I will pressure test in the Morning. It has rained good in the last week..

Rick

 

There is definitely a chance that the AC box drain is plugged and giving you some noise. It rained a lot here too last week and the fall is the time for pine needles and other crud to clog your drain. However, you said that your heat was not working so I wonder if your heater core isn't just air bound. Does it make the noise when you rev the engine when sitting still or only as you make turns?

John

 

only on turns....usually I cant hear it anymore after a few miles.

Rick

 

Hmmm. If it made the noise whenever the motor revved up I'd lean more towards it being air bound but if it does it around turns then I'd lean more toward a plugged drain on the AC evaporator side or a leak from the heater core that simply hasn't begun to drip yet. I'd start by checking the drain and go from there.

John

 

Drains clean, Antifreeze level is full. Once at engine temp, the heater hoses are both warm. Not HOT, but not cold. I can touch them bare handed for as long as I want.

So now where to look?

Rick

 

Could the sloshing sound be the door in the HVAC system that controls the hot/cold blend? Maybe it came off its linkage and is slapping around? That would explain the noise as well as the no heat.

John

 

I don't think so, I can change it from hot to cold and feel the difference.

tonight, I had the heat turned off, if you turn it on low fan its a little warmer, but as soon as you turn the fan up, you get a blast of heat, then it cools down quick. And I also noticed my truck is taking longer to warm up and its cooling down at idle/traffic lights etc. Never did that before, I always stayed between 185-95

Rick

 

There was a tech tip from Dodge to relocate the heater hose to the next plug in the cylinder head. Just swap the plug with the hose connection then install another longer heater hose, this stops the coolant cavation in heater core and the noise. I would flush the heater core out by back flushing it when you have the hoses off. This should help you with your heater core not getting hot problem.

 

I know its a mechanical pump on these trucks but you may want to check the water pump. It sounds to me like the fluid is either low(which you said it wasnt), has air pockets in it, or the water pump is not circulating the coolant

 

On mine, it was just low coolant level and an air bubble would flow through the system and make that sound. Like water running at passenger side. I just took off the radiator cap when cold and started it and let it run. Shook it pretty good a couple of times and as the air bubbles came to the surface in the radiator topped it off with coolant mix. Took a few minutes but finally got most of it. No more running water sound! Do the simple stuff first! Also can see if the pump is pushing fluid at that time.

 

Sounds like it's time to change your thermostat. Easy job, bet you'll find the inner rubber seal has come off and is keeping the stat from closing.

As for the gurgling sound, both my trucks have been doing it on cold start up for 13 years.
I don't pay it any mind.

 

Ahhhh. That was some very crucial info. You should definitely get a new stat first off. Order an OEM one from a Cummins dealer.

John