My 2012 Dodge Journey has what seems to be a common problem with debris in the coolant from the casting process of the block, which affects the ability to produce heat from the heater core ... I've had the heater core cleaned several times , then a heavy duty engine flush, then added one of the 5/8" inline coolant filters which still clogs up within a day or 2 .... just had the coolant replaced again thinking that we could get more of the debris out .. cleaned and replaced the coolant filter but it still clogs within a short period of time .. the Dealership is saying that the block needs to be "cooked" to get rid of what appears to be a large about of gunk ... I am thinking that this small inline filter is just not large enough to do any serious filtering BUT I can't locate anything about any type of larger filtration systems that someone may have tried or even DIY'd .... If this is such a common issue what have other owners been doing ???

 

Not sure if the Dealer sold you any additive to install before they did the flush? or even how the flush was performed?
Always better to install a cleaner, drive and then flush the system... Also Back Flush... Agitate as much as possible and reflush.. And then add coolant and Distilled Water to the system...
Flushing the heater core is also good as well...

Did they sell you a cleaner similar to this one?
https://justicebrothers.com/products...ystem-service/

 

Truthfully I don't know if they added a cleaner as you mentioned ...

 

Just a suggestion.... If you have a local radiator shop near you... Maybe worth asking them to perform a flush and back flush of the system... I think you will have better results.... Sometimes the dealer is only as good as the tech that works there....
The small filter on the hose is only going to filter a very little amount going to be hard to get ahead of the rust and trash in the system....
Just my 2 cents