Anybody Have Any Issues with the new HD's yet?

[Bozo]

I've found my a/c works best by NOT using the MAX A/C selection. I lower the temp all the way down and it seems to cool better.

If this is the case, it is azz backwards and FCS needs to rectify the situation. Max a/c should always be quicker to cool as it’s supposed to recirculate inside the cab. My father n law never could grasp that concept, for whatever reason. I realize this is common knowledge, but it irks me how so many details/ flaws are overlooked/not fixed, in these overpriced trucks.

 

[2019_Ram]

Pay attention when using the A/C. Seems there is nothing but poor programming there to compliment the inadequate A/C performance. On mine, when in auto mode, the blower will have a +1 speed faster than in any other mode. Switching to Max A/C or Manual fan mode will knock the blower down a speed. Where the manual mode and Max A/C blower speed tops out, the Auto mode has a hidden speed that makes it blows more air.

This inadequate A/C is by far my biggest complaint with this truck and with the hot and humid weather coming in soon, may become a serious safety issue as it is unable to cool the cabin in any sort of reasonable time.

 

[Brutal_HO]

They really need to dumb this A/C control down a bit when not on Auto.

One of my biggest gripes would be changing from all dash vent to split anything disables the recirc (max A/C). What in the literal F***?

I know it's hard to believe, but I know how to correct a fogging windshield.

P.S. FCA. The heater blower vents onto the windshield suck too. First time I drove my truck in freezing rain, it could not keep a (preheated cab) windshield clear of ice. Sad that this $90K truck is worse than my 04.

P.P.S. Lose the stupid plastic bed and tailgate cap rails. What a POS system. I wanted to do a Line-X over the rail spray and couldn't unless doing extension bodywork to fill the stupid holes in the panels. UV protective maintenance aside, they're going to look like crap in short order. Who thinks up this garbage?

 

[NordicNevs]

Just to make sure it looks like this for your guys right? AC with recirc setting

Cause in this setting it works great

I never use Max ac and I’m down here in NM

No issues yet with my cooling.


Sent from my iPhone using Tapatalk

 

[jakalafus]

Mine does a good job until 103 outside. My issue is the evap sensor says 39 degrees per the computer and my temp gauge in my vent won’t go cooler than 61 In any Mode, fan setting, temp or recirculate combo. Yesterday my buddies gmc was 48 at his vent.

 

[thestuarts]

I've found my a/c works best by NOT using the MAX A/C selection. I lower the temp all the way down and it seems to cool better.

I noticed the same thing! Max A/C doesn't cool as much as regular A/C turned all the way down with recirculation enabled and fan on high.

 

[Brutal_HO]

Mine does a good job until 103 outside. My issue is the evap sensor says 39 degrees per the computer and my temp gauge in my vent won’t go cooler than 61 In any Mode, fan setting, temp or recirculate combo. Yesterday my buddies gmc was 48 at his vent.

QFT.

@RamCares Where is FCA on this shortcoming in the HVAC system? This seems to be a widespread issue.

 

[2019_Ram]

Decided to take the plunge today and temporarily bypass my heater core. 2019 2500 6.7l diesel. There was a significant difference in the performance of the A/C and its ability to cool the cabin.

Before the temporary bypass I was seeing on average 56* vent temps with an outside temp anywhere between 60*-80*.
Bypass installed today, I was seeing 43-44* vent temps with an outside temp of 86* and ALFAOBD showing an EVAP temp of 37-40*.

A 12* vent temp difference is very significant and makes a very noticeable difference in the amount of time the cab takes to cool down. It is unacceptable to be hacking a valve in the cooling system of an $80k truck, just to have adequate A/C performance. Anyone else want to take the plunge and temporarily bypass your heater core in the pursuit of adequate A/C? And is there any speculation as to why RAM is unable to come up with a simple solution of using a small 12v coolant shutoff valve and a little programming to make it work seamlessly with the HVAC system?

 

[jakalafus]

Decided to take the plunge today and temporarily bypass my heater core. 2019 2500 6.7l diesel. There was a significant difference in the performance of the A/C and its ability to cool the cabin.

Before the temporary bypass I was seeing on average 56* vent temps with an outside temp anywhere between 60*-80*.
Bypass installed today, I was seeing 43-44* vent temps with an outside temp of 86* and ALFAOBD showing an EVAP temp of 37-40*.

A 12* vent temp difference is very significant and makes a very noticeable difference in the amount of time the cab takes to cool down. It is unacceptable to be hacking a valve in the cooling system of an $80k truck, just to have adequate A/C performance. Anyone else want to take the plunge and temporarily bypass your heater core in the pursuit of adequate A/C? And is there any speculation as to why RAM is unable to come up with a simple solution of using a small 12v coolant shutoff valve and a little programming to make it work seamlessly with the HVAC system?

I saw in another forum concern about the routing and what it might do to the motor etc. in the HDs... Have you noticed anything weird at all?

 

[Deleted member 80]

Decided to take the plunge today and temporarily bypass my heater core. 2019 2500 6.7l diesel. There was a significant difference in the performance of the A/C and its ability to cool the cabin.

Before the temporary bypass I was seeing on average 56* vent temps with an outside temp anywhere between 60*-80*.
Bypass installed today, I was seeing 43-44* vent temps with an outside temp of 86* and ALFAOBD showing an EVAP temp of 37-40*.

A 12* vent temp difference is very significant and makes a very noticeable difference in the amount of time the cab takes to cool down. It is unacceptable to be hacking a valve in the cooling system of an $80k truck, just to have adequate A/C performance. Anyone else want to take the plunge and temporarily bypass your heater core in the pursuit of adequate A/C? And is there any speculation as to why RAM is unable to come up with a simple solution of using a small 12v coolant shutoff valve and a little programming to make it work seamlessly with the HVAC system?

This confirms what I thought was going on, the A/C is fighting heat infiltration. Thanks for taking that step. Sadly, I don't see them addressing this at any point. They have our money, so it's "system working as designed". Except it is designed poorly.

 

[2019_Ram]

jakalafus,

No known side-effects, besides AC that was actually cold. I didn't actually block the flow of coolant, but rather bypassed the heater core with extra piece of heater hose. Looking at the layout of the coolant hoses, I think we would probably be ok actually blocking the heater core inlet off the head with a single valve. It doesn't look like the turbo cooling is fed from the heater core output, like in early 6.7l engines. But someone please correct me if my statement about the turbo cooling lines is incorrect.

 

[thestuarts]

Anyone else want to take the plunge and temporarily bypass your heater core in the pursuit of adequate A/C?

What are the steps?

 

[Great White North Eh]

jakalafus,

No known side-effects, besides AC that was actually cold. I didn't actually block the flow of coolant, but rather bypassed the heater core with extra piece of heater hose. Looking at the layout of the coolant hoses, I think we would probably be ok actually blocking the heater core inlet off the head with a single valve. It doesn't look like the turbo cooling is fed from the heater core output, like in early 6.7l engines. But someone please correct me if my statement about the turbo cooling lines is incorrect.

Could you show some picks of your engineering please? I used to follow the 1500 side of this forum when I was planning on ordering a rebel and there was a huge thread on pinching of the heater hose. It apparently it’s an FCA truck problem not just HD issue. Maybe that monkey engineering department can be switched to another non truck project and screw it up

 

[Brutal_HO]

Decided to take the plunge today and temporarily bypass my heater core. 2019 2500 6.7l diesel. There was a significant difference in the performance of the A/C and its ability to cool the cabin.

Before the temporary bypass I was seeing on average 56* vent temps with an outside temp anywhere between 60*-80*.
Bypass installed today, I was seeing 43-44* vent temps with an outside temp of 86* and ALFAOBD showing an EVAP temp of 37-40*.

A 12* vent temp difference is very significant and makes a very noticeable difference in the amount of time the cab takes to cool down. It is unacceptable to be hacking a valve in the cooling system of an $80k truck, just to have adequate A/C performance. Anyone else want to take the plunge and temporarily bypass your heater core in the pursuit of adequate A/C? And is there any speculation as to why RAM is unable to come up with a simple solution of using a small 12v coolant shutoff valve and a little programming to make it work seamlessly with the HVAC system?

So lemme get this straight.

FCA is feeding hot coolant into the cabin in a manner that it cannot be isolated from the cool air during a MAX AC or low temperature AC demand?

What in the actual F***?

 

[2019_Ram]

I have already pulled my test setup off the truck tonight, as we are expecting some cooler weather soon.

Here's what I did. Picked up another heater hose connector from the parts house and some 5/8 heater hose. I used some well placed clamps to pinch off the heater hoses and minimize coolant loss. Have everything ready because the radiator is actually higher than the heater hose connection. I did the connection on the head first, then the stand pipe. I lost very little coolant with the well placed hose clamps and having everything ready to quickly swap back on, probably under a cup.

The test setup completely bypassed the heater core. Outlet on the head to stand pipe. It looked to me like the turbo gets coolant from the bottom and then dumps to the standpipe thru the braided hose below the heater core output hose. If I didn't miss something, it looks like one could temporarily clamp off the hose coming from the head and get nearly the same result without needing to reroute hoses.

After reconnecting the heater core and a short drive, the vent temps are back to 56* with it being 73* outside.

 

[Great White North Eh]

Right on. Keep up the mad science!

 

[thestuarts]

It looked to me like the turbo gets coolant from the bottom and then dumps to the standpipe thru the braided hose below the heater core output hose.

That is correct. Coolant enters the turbo from below in hose #4 in this diagram.



Coolant leaves the turbo from above in hose #2 in this diagram. It dumps to the standpipe as you stated.

 

[2019_Ram]

With the info thestuarts had provided, I think anyone that wants to test this would be able to safely clamp off the heater input hose, just as it comes off the engine head. If you go this route, be careful not to damage or crush the plastic heater connector.

It seems like this might be the easiest place to put a valve off some sort to be able to control the coolant flow with minimal modifications. Maybe a cable operated one, that could be controlled from within the cab?

 

[thestuarts]

With the info thestuarts had provided, I think anyone that wants to test this would be able to safely clamp off the heater input hose, just as it comes off the engine head. If you go this route, be careful not to damage or crush the plastic heater connector.

It seems like this might be the easiest place to put a valve off some sort to be able to control the coolant flow with minimal modifications. Maybe a cable operated one, that could be controlled from within the cab?
View attachment 4868

There isn't a lot of hose to work with on the heater core input hose side. Do you think it would be safe to put a valve on the heater core egress hose, or would that pressurize the heater core leading to other problems?

 

[2019_Ram]

I don't know how effective it would be on the output side. My preference would be on the input side, but I have no real reason as to why it would have to be there. With a valve on the input side only, the heater core would still see the pressure of the cooling system and some warm coolant through the output hose, but avoid positive hot flow in. Seems they have plenty of industrial versions of this engine that don't have a heater core and the heater core output plugged at the head.

My thought was to get a compact shutoff valve, that could be stuck on the input side, and be shielded a bit more from the heat of the exhaust and turbo. In my head it would go like: engine head -> heater core connector -> very small section of heater hose to couple connector to valve -> original unmodified hose to valve output. This would allow a quick return to stock if there ever was any need. When I had it disconnected the other day, I had enough play to pull it toward the front of the truck and would have been able to easily access the clamp. There also seems to be enough play in that hose to add an inch or two and not negatively affect anything.