Low air output in cab and not very warm.

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APetras

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2014
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6.7l tuuuuuuurbo diesel
Hello everyone, I'm having an issue with my 2014 ram 2500 6.7l cummins Mega Cab Laramie. First off, I'm located in ND and it's cold. My hot air in the truck doesn't seem to be getting very hot, and on top of that I don't get much air flow unless I turn on Recirc. With Recirc on it blows air like crazy, almost like it has a whole extra fan speed, but my windshield frosts up on the inside. I'm leaning towards a plugged up evap coil and probably needing a heater core flush or replacement. I don't believe I have a cabin air filter in my truck either so I'll probably order the kit from Geno's garage.

My engine temp appears to be fine as it climbs up to the midway hash and then the t-stat opens up and the temp drops a bit. I am going to look for a winterfront for the truck, but I know this won't solve my cabin air issues.

Any Ideas from you guys would be great, this is my first Ram truck and I've owned it now for a few years, but aside from a Delete and a fuel pump I really haven't worked on it too much.

Thanks!
 

TheEnder

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How many miles? My ram had a problem with the heater on the drivers side not working at all and when heat was selected the air would barely blow out from the drivers vents at a cool temperature and it would blow out strong from the passenger vents screaming hot. Truck doesn’t have dual climate either.

I got it fixed, i had to flush the cooling system. Id try that.
 

gofishn

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2022 Ram 1500 5th Gen, Big Horn, 4X4, Crew Cab, 6'4" Box
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hemi 5.7L, 345 cu in
when was coolant last changed?

If forever and a day, change it.
Completely. if do not know how, ask or youtube it.

Frost on inside when in recirc? That is worrisome.
Any lowering of coolant in the coolant reservior levels?

Recir should give you an extra fan boost, no longer bring in outside air into cab.
Bland door closes so temps should geet warmer as you are warming already warmer air.
like Recir A/C in reverse.

However, could also be a blend door issue as well, possible your blend door is not closing enough or at all. when in anything other than recirc mode.

Plain cardboard will get you there, in front of raiator, for now.,

2014 should not have a cabin air filter kit, from factory but if you did not buy it new..... check adn se. remove glove box and see.

let us know each step and what you find.
 

White six four

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If your truck doesn't have a cabin air filter I wouldn't worry about it til warmer months. If the previous owner installed one and it's dirty then that could result in poor airflow. I added one on my 16 and when the snow flies I take it out since I don't see a point in having it in there. No dirt/dust getting kicked up and even a new filter restricts airflow a little. Come spring time I buy a new one and put it in.

Like others have said if you don't know when the last time the coolant was flushed flush it out. And I'd flush out the heater core while you're at it.
 

Flip-er

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5.7 Hemi
How many miles? My ram had a problem with the heater on the drivers side not working at all and when heat was selected the air would barely blow out from the drivers vents at a cool temperature and it would blow out strong from the passenger vents screaming hot. Truck doesn’t have dual climate either.

I got it fixed, i had to flush the cooling system. Id try that.
I am having same issue sometimes, I am going to have cooling system flushed and heater core back flushed.
all this started after the cam and lifer failure i had and had all that replaced.
mech thinks air pocket is the cause.
I was bout due for a coolant flush anyway, so no biggie
 

Flip-er

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I am having same issue sometimes, I am going to have cooling system flushed and heater core back flushed.
all this started after the cam and lifer failure i had and had all that replaced.
mech thinks air pocket is the cause.
I was bout due for a coolant flush anyway, so no biggie
Had my coolant flushed along with heater core.
Fixed my problem
went from low flow and about 112 degrees out of drivers venys to
full air flow and 146 degree air coming out.
Hope it lasts
 
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APetras

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Thanks for the responses guys and sorry it's taken me so long to reply. I replaced the water pump with an aftermarket unit probably 35k miles ago, and then the dealer had a recall on the water pump and in order to get the recall cleared I had to take it in to them and they went ahead and put in their recommended replacement water pump. Out side of that, the only other dealings I have had with the Coolant have been replacement of that Y-Pipe that is notorious for cracking. I'm thinking maybe I will call in to the local repair shop and see if they could do a coolant flush for me and back flush the heater core.

I will probably just wait until this summer to tear the dash out and have a look at the evap coil, but I definitely think the fins on it are probably clogged up because there just isn't nearly as much air flow out of the vents as I feel there should be.

My truck as approximately 175k miles on it. I wouldn't say I do a TON of driving on gravel, but I do like to hunt alot, and we live out of town in North Dakota where there is always wind to kick up dust...
 

mtnrider

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You most likely have a clogged heater core (extremely common on these trucks) causing your heat issue. As far as air flow, it was never good to start so unless you noticed a sudden change it's probably normal. You can drop the fan real easy (3 screws) and look into the evap coil with a mirror or phone etc to see if it is clogged.
 
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APetras

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You most likely have a clogged heater core (extremely common on these trucks) causing your heat issue. As far as air flow, it was never good to start so unless you noticed a sudden change it's probably normal. You can drop the fan real easy (3 screws) and look into the evap coil with a mirror or phone etc to see if it is clogged.
Thanks mtnrider. I didn't realize it was so easy to drop the fan and look in. I'll probably do that as well. Waiting on a local shop to call me back and tell me when they can get it in for the coolant flush/core back flush
 

Dean2

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Your windows fogging on Recirc is perfectly normal. Happens everywhere it is cold as you are not getting rid of the moisture. The AC runs in defrost mode specifically to dry the air, I run it in normal heat mode for same reason.

Heat in the older diesels was always an issue so you have to make sure everything is top drawer. Check the air intakes below your wipers, snow build up, or them being plugged with leaves or other stuff will severely restrict the outside air that is available. The advice to change coolant, flush system and heater core is spot on. The heater core flush only works about half the time, be prepared to have to replace it the other half the time.

The winter front will help a lot with heat at highway speeds. On my 96 I got the grill inserts and used a piece of carpet between the Rad and grill, and the V10 produces way better heat than the diesel does. Even a piece of cardboard between the rad and grill will help do the job till you can find what you want.


Generic picture of inserts. Easy to put on and off, look good, and don't flap around like most grill covers.
th?id=OIP.jpg
 
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APetras

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So I called a local shop today and they asked for my plate number. They looked up my truck and informed me that the heater core in my truck can not be back flushed because it is a parallel core. Personally I have no clue what they are talking about. Does this make any sense to you guys. My next call is going to be to the local Dealer as the first place I called was just a mechanic shop.

They then proceeded to quote me $235 for a core and $950 in labor to replace it.... I told them no thanks I'll do it myself.
 

Dean2

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Order the Core from Rock auto, even if you never did one it isn't going to take you 6 hours.


Heater Core Flush Procedure​


Dodge RAM heater core issues.

We see common issues with a temperature differential between the driver and passenger sides of the RAM truck, or lack of heat on both sides. The root cause of the problem is that the heater core is a parallel flow core, meaning the the water comes into the top and down multiple channels to the bottom. Most cores are serpentine flow and you’ll get equal pressure and flow across the entire core. You can check the flow of the heater core by letting the truck get to operating temperature with the heater off. When you cut the heater on, if you get a burst of warm air and then it dissipates, this is a strong indication of the heater core not providing heat as fast as the fan is extracting it.




The core is the narrowest constriction in the flow path and will act almost like a filter for any gunk in the radiator system. Dodge recommends routine radiator flushes, but no one pays attention and does this. If you are as negligent as us, this could be a cause of the problem. We also see issues when any work is done on the radiator system. Just replacing components or wiggling heater hoses can product particulates. You should always do a radiator flush anytime work is done on the coolant system.




The pressure is not equal across all the parallel channels and the back half will tend to “catch” the gunk and you’ll get a temperature gradient across the core which shows up as different temperature for the passenger and driver. It will get progressively worse and you can get to a point where you don’t have good heat on either side. Even with minimal flow the two heater hoses will get hot and you can’t really gauge the heat in the core by feeling the two hoses on a hot engine. What you have to do is cut the heat/fan on full blast and feel the two hoses from a cold start. The hoses should warm up at the same rate and get uncomfortably hot in a few minutes. This is a common problem and just doing a good flush on the core is probably not a bad idea if you have any concerns with temperature.




Here’s what we recommend to get the core flushed correctly. Since the flow is parallel, if you just get a few channels open, you’ll get good flow through the core. You can’t put enough pressure on the core to clear all channels once a few are open. To get to all the channels, you have to attack the problem chemically.
1. Isolate the core by either removing the heater hoses or just buy two brass garden hose repair kits at Home Depot and cut the hoses.
2. Flush the core backwards and forwards with a garden hose.
3. Fill the heater core with Prestone radiator flush and let it sit a couple of hours or overnight. We recommend the Prestone liquid flush because it works. We met the Prestone VP of engineering at SEMA a couple of years ago and he agreed with our analysis and solution. He said he would take our information back to their lab and look into a kit for just this issue, but I haven’t seen anything come of it.
4. Flush the chemicals out.
5. The trick is to swap the heater hoses such that the core will flow “backwards” when you reconnect.
6. If there is still gunk floating around in the radiator, the problem will occur again. We’d suggest just connecting the two heater hoses together and do a good flush on the radiator independent of the heater core.
7. Going forward it’s a good idea to do a flush every 12-18 months and swapping the hoses back each time.
8. If this helps, but not enough. It’s like the old High School Joke: “It’s a long way to the cafeteria, you have to flush twice…”




If this doesn’t help, the next concern is the blend doors and our replacement is a complete fix for any door issues. This is about a thousand dollars worth of free advice and we’d appreciate you keeping us in mind when you do see door issues.
 

Flip-er

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Raleigh, N.C
Ram Year
2013 Big Horn 4x4
Engine
5.7 Hemi
Order the Core from Rock auto, even if you never did one it isn't going to take you 6 hours.


Heater Core Flush Procedure​


Dodge RAM heater core issues.

We see common issues with a temperature differential between the driver and passenger sides of the RAM truck, or lack of heat on both sides. The root cause of the problem is that the heater core is a parallel flow core, meaning the the water comes into the top and down multiple channels to the bottom. Most cores are serpentine flow and you’ll get equal pressure and flow across the entire core. You can check the flow of the heater core by letting the truck get to operating temperature with the heater off. When you cut the heater on, if you get a burst of warm air and then it dissipates, this is a strong indication of the heater core not providing heat as fast as the fan is extracting it.




The core is the narrowest constriction in the flow path and will act almost like a filter for any gunk in the radiator system. Dodge recommends routine radiator flushes, but no one pays attention and does this. If you are as negligent as us, this could be a cause of the problem. We also see issues when any work is done on the radiator system. Just replacing components or wiggling heater hoses can product particulates. You should always do a radiator flush anytime work is done on the coolant system.




The pressure is not equal across all the parallel channels and the back half will tend to “catch” the gunk and you’ll get a temperature gradient across the core which shows up as different temperature for the passenger and driver. It will get progressively worse and you can get to a point where you don’t have good heat on either side. Even with minimal flow the two heater hoses will get hot and you can’t really gauge the heat in the core by feeling the two hoses on a hot engine. What you have to do is cut the heat/fan on full blast and feel the two hoses from a cold start. The hoses should warm up at the same rate and get uncomfortably hot in a few minutes. This is a common problem and just doing a good flush on the core is probably not a bad idea if you have any concerns with temperature.




Here’s what we recommend to get the core flushed correctly. Since the flow is parallel, if you just get a few channels open, you’ll get good flow through the core. You can’t put enough pressure on the core to clear all channels once a few are open. To get to all the channels, you have to attack the problem chemically.
1. Isolate the core by either removing the heater hoses or just buy two brass garden hose repair kits at Home Depot and cut the hoses.
2. Flush the core backwards and forwards with a garden hose.
3. Fill the heater core with Prestone radiator flush and let it sit a couple of hours or overnight. We recommend the Prestone liquid flush because it works. We met the Prestone VP of engineering at SEMA a couple of years ago and he agreed with our analysis and solution. He said he would take our information back to their lab and look into a kit for just this issue, but I haven’t seen anything come of it.
4. Flush the chemicals out.
5. The trick is to swap the heater hoses such that the core will flow “backwards” when you reconnect.
6. If there is still gunk floating around in the radiator, the problem will occur again. We’d suggest just connecting the two heater hoses together and do a good flush on the radiator independent of the heater core.
7. Going forward it’s a good idea to do a flush every 12-18 months and swapping the hoses back each time.
8. If this helps, but not enough. It’s like the old High School Joke: “It’s a long way to the cafeteria, you have to flush twice…”




If this doesn’t help, the next concern is the blend doors and our replacement is a complete fix for any door issues. This is about a thousand dollars worth of free advice and we’d appreciate you keeping us in mind when you do see door issues.
Thank you for AWESOME write up.
You taught me alot there, so Thank You
 
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