707dumb

Well looks like the grand caravan still has a manual. The only other is for a Challenger. Wtf?!
Repair manuals for two Dodge models!? Anyway, I found one here(for the grand caravan)......
 
https://haynes.com/en-us/dodge/grand-caravan/2008-2018

from what iv heard there is an online book or manual but it has to be purchased, other than this is all iv heard, google be thy friend...good luck

It never hurts to do preventive maintenance.  It is cheaper to change the transmission fluid than to change the transmission.  Go ahead and do it.
 
The coolant is extremely poisonous to animals.  Make sure that you do not have any of it on the driveway or garage floor.  Your pets love the taste of it.  Only problem is that it kills them.  It is also bad for children.  Be careful.  It is recyclable.  Just needs to be cleaned.  Any radiator repair shop will probably accept it.  If it was my vehicle, I would take it to a shop and have it flushed.  That way it cleans all the sludge out of the system.  Might as well get it done right and not have to worry about disposing of the material.
 
Good luck.
 
mechanical-idiot

I should have waited to take it in. I could have used that kit and had evidence that it's the gasket between the block and head
 
 Auto shops should figure this out. And I did mention head gasket when I brought it in. They thought I was going to get lucky and just did the thermostat and bled the air. Unfortunately that did not do it. So it's back in the shop. Just waiting......

I have one, I got in the mail after the van was in the shop. And the shop told me there is no combustion gases in the antifreeze. So if I check it myself I should get the same results......

Radiator, water pump, blockage/air bubble, blown head gasket. I’m betting on the head gasket.

It is common on the 3.6. the rocker arms bearing will wear out. There's plenty of YouTube videos on how to fix it but you really do have to be mechanicaly inclined. The hardest part about the job is disconnecting everything in the way.

Thanks guys, it's in the shop already. Just love the input from people that know way more than me lol. I wish I could do the job myself, but I would mess something up, not torque the bolts correctly or something. I really appreciate your input!

Thanks guys, it's in the shop already. Just love the input from people that know way more than me lol. I wish I could do the job myself, but I would mess something up, not torque the bolts correctly or something. I really appreciate your input!

think all he wants to do is ask  questions, start with the simple things or just put in to a garage and let them check it out.

It needs to vent somewhere when a over pressure condition exists. If yours is blowing coolant out of that hose, there is something else going on to cause that condition. If the thermostat is good, the water pump is good, the cooling fan is working, it’s time to check the head gaskets as mentioned. 

i just hobbled out to my journey and actually there is no hose that connects to that ,it must just be a vent as on my 2014 3.6 the same thing just the  the plastic elbow that you have pictured. the return hose must be under the bottle or is the same hose for the overflow.

i wonder if this will work on a journey as your cap is on the coolant bottle not on top of the rad like shown in the video?????

it returns coolant back to the rad

Not so sure, might be the overflow?

well just run by your local dealership they can show you where it goes ,the name of it and even price one at the parts window or just look at one on the dealers lot and see for yourself , i have a bad knee so kind of hard for me to go look at mine in the garage for you  as well looks like you have a very dirty or leak as well from your picture