2018 ram 3500 tradesman 6.4l hemi no heat

Hey just trying to get some info. Just purchased this truck Jan 2022 and just figured out that the heat is not working like it should. I am lucky living in florida we don't get as bad a weather as other northern an Midwest states. It seems temp of about 45 and up to 70 degrees outside the heat seems to work but less than 45 not so much blows cold. And yes we do get below 45 outside LOL. My gauges show approx 203 to 215 and stays around 208 or so for coolant temp. The indicator usually stays straight up and down after it warms up. Which I am thinking its normal for this truck. Coolant has a purplish tint to which I think is right color and is showing normal range in overflow tank when cold and hot.I have 70000 miles on it. I confused not sure how all my indication seem correct but stupid thing blows cold. Sorry for long conversation but just trying to get some ideas and give enough info.

First find the 2 hoses going through the firewall on the passenger side after you have driven the truck enough to get it warmed up to operating temp.
They should both be hot !

If one hose is noticeably colder than the other, you should watch a Youtube video on back flushing the heater core

Next step is to visibly watch the 4 HVAC Actuators moving, which takes a few parts to be removed, very simple job

Thanks I will start with heater core. Not sure what the 4 hvac actuators are but will research.

It's most likely the heater core. You will probably find the heat is better on the passenger side. The way these are set up the driver side heat comes from the bottom of the heater core and the passenger side heat comes from the top. What happens is sediment settles in the bottom. Clogs it up. You get less heat on the driver side. You can try flushing it. Most times the heater core will have to be replaced.

That s crazy on a 2018 never had issues with any other vehicle like this. With only 70000 miles.

bigdodge said:

It's most likely the heater core. You will probably find the heat is better on the passenger side. The way these are set up the driver side heat comes from the bottom of the heater core and the passenger side heat comes from the top. What happens is sediment settles in the bottom. Clogs it up. You get less heat on the driver side. You can try flushing it. Most times the heater core will have to be replaced.

Click to expand...

This I have replaced 5 so far on 4th gens no idea why it does this Of course check the basics first coolant level, tstat, Bleed system, heater core flush ect.

I don't know what's in that coolant but it alone clogges these things. The whole system needs flushed every couple years in my opinion. If it's left to sit too long it become almost solid.

Thats good info I bought used so thats next on list to complete as soon as possible and hopefully rejuvinate heater core without needing to replace.

Well started the backflush on heater core while warming up truck i felt air coming out of this tube. No idea what it is for any help? It sits right below heater core hoses.

That's the condensation drain for the ac

Is suppose to blow air out of tube?

littlebiscuit said:

Is suppose to blow air out of tube?

Click to expand...

It's on the positive side of the fan, so yes it normal. Helps push condensate out when the AC is running.

Hey there.

Did you ever find a resolution to this problem? I have the same truck (2015), and am having the same issues. Did the heater core flush work? I'm looking down the road of a broken blend door or connection to the blend door actuator, but I wanted to know if you fixed it with a heater core flush.

Any help would be greatly appreciated!

It seemed to help from what I can tell. The weather here only dropped below 50 degrees for a few hours after I did it. True test unfortunately will be next winter. But when the truck warmed up it seemed to get hot better than it was. I did rig up a couple of hose and poor some CLR in hoses let them set an hour or so then rinsed the hell out of core running water both ways through core.