Heat Sucks

[robert kaylor]

Ok now that winter has finally set in I've noticed the heat on my 2013 4.7 isnt working too well anymore. I've made sure to check the coolant level and its good. I've flushed the heater core to make sure it wasnt blocked. No fuity smell or coolant loss that would indicate a leaking heater core or leak elsewhere. Also both hoses to the heater core are getting equally warm when running.

Even thought maybe the thermostat was hanging open so went as far as replacing that. But nothing as of yet has seemed to improve it. I know that supposedly there have been some issues with blend doors needing to be re-calibrated. But I can't seem to find a process for the 2013+ that works.

So anybody go any suggestions on something I might be overlooking before I take it in and let the shop have a go.

 

[Burla]

Was the truck flushed regularly? Replace heater core? Coolants don't contain detergents, running rmi-25 will take any slime and deposit it into over flow, so replacing coolant wont do anything, new coolant wont clean better then old coolant like engine oil does. Can you feel the coolant through hose in and out to feel good flow?

 

[68PowerWagon]

I am having the same issues with my 2016 2500. Only 50k on it but I did a flush anyway & that did not help. I have also heard that it could be the blend door. That would suck because the dash has to be dismantled to get to it. I am going to just tuff it out for now. Really dreading getting into that!

 

[Tach_tech]

Just because both hoses are hot to the heater core doesn’t mean it’s not plugged. If only part of the heater core is plugged you’ll still get flow through the rest of the core but only that portion of the heater core will heat up and you’ll have poor heat output.

 

[robert kaylor]

Ok so sounds like giving it another go flushing the heater core may be worth my time. can i use something like the prestone or blue devil radiator flush in the heater core alon.

 

[Ribtipram]

Just disconnect both hoses and flush with the garden hose. If the core is plugged up u should be able to tell by the crappy flow coming out. If its flowing ****** you will be able to tell.

 

[jws123]

I fought this on all of my rams was never the blend doors or calibration flushed many times the only cure is a new heater core it really is not a bad job at all it took me 1 day. I cut the heater core i took out of my 2011 open and half of it was clogged solid. I get a toasty 150f out my vents now.

 

[hotkarl]

Son went through similar thing with an old Cherokee. Weak heat.
Brought it to shop, they "flushed the system" and he had lukewarm heat so he was satisfied, thought that was it and all that could be done.

This winter I was driving in it with him and I was like what's up with the heat thought you got it fixed?
So he's like yeah. And I'm like no, it should be melting your toes off.

So I poked around a bit and everything checked out ok at face value.
He took it back to shop(different one this time) and they sent it to a radiator shop and they flushed it and that solved it. Heater core was all gummed up. After that, it did indeed melt toes. He couldn't believe it.

Pray to god it's not the mechanicals, because you need to remove the dash.
Expensive job to send it out, or a whole Saturday if you do it yourself.
And, because it's such a suck job, while the whole thing is ripped out it's smart to replace EVERYTHING.

 

[Burla]

This has been my go to coolant system product since 1990's, all I can say it does exactly what it says it does, if you have slime in the system, this removes it and deposits it in overflow where it is trapped until you remove it..