HVAC Removal with Pictures

[KenChristensen]

Thanks bunches! I have done this once, but I just started taking stuff off. I have to help do this on a buddys pickup. This time I wont have every panel that comes off, off.

 

[MAshley]

Sorry to ask, but when this happened and you turned the heater on high did the fan motor Vibrate a lot ? I have this going on right now and I have a trip to take ... so Im not to happy about the whole thing

At least the parts are cheap. . hehe

 

[LesStallings]

No vibration for me...

 

[Semicrazy]

I have this problem right now...



I can only get air out of the dash vents, nothing out of the defrost or floor vents.



Has anyone done this without breaking the A/C connections? I hate taking my truck to the shop for anything. I would prefer to do it all myself.

 

[SOLER]

5127758AA - Lower HVAC housing - $43

5073964AA - Defrost door - $19

5019632AA - Coupling - $7

68004226AB - Recirculation housing w/ door and actuator- $20



I'm about to do this. Probably over Christmas break. Anyone that has done this lately, are these the only parts needed? What about the queston above about the blend door? Is there a fifth part? Thanks.



Oh, and what about the cost? I noted above that the housing is twice as much as $43. Have these parts gone up in price?



SOLER

 

[SOLER]

I answered my own question. The blend door is part number: 5073992AA, and my dealer says $28. 60 for it.

 

['strokeThis_'07]

This is the best write up Ive seen yet... gotta do this to my 03, as its hit or miss whether or not it goes to defrost, sometimes it does sometimes it doesnt (when I need it it doesnt, when I dont need it it does... ) Now I can save a grand and do it myself... gotta roll the Challenger outta the garage and roll the truck in

 

[KenChristensen]

I just paid 145. 00 for all the parts, and the blend housing was 115. 00 list price. neither myself or my buddy have had the vibration problem, but he has had it work just fine at some times, and other times the thing can't keep the windshield ice free in the lightest sleet. I'm guessing we will find broken parts on the door and the big housing.

 

[KenChristensen]

If I remember right the fan comes out with just a couple screws and a connector. Could just have stuff (leaves, twigs, dirt) on the squirel cage.

 

[PLohr]

Thanks for the write-up. Just did this job to replace the blend door, mode door, and recirculation housing in my 2003. Sure made the job easier.



Some improvements that can be made anytime the

HVAC unit is removed are below.



1. Get a piece of screen and about 8 #6 x 3/4" pan head screws.

I used stainless steel screws to reduce the chances of rust.

I decided to use aluminum screen since I thought it would

be more durable. Fiberglass may be durable enough - that's

your call. Remove the outside air intake pipe from the firewall.

This is the piece that is rectangular and passes through the

firewall. Form the screen around the outside air intake pipe, on

the outside air side, and cut as necessary. Use the screws to

fasten the screen to the intake pipe. This will stop any debris

from finding its way into your HVAC unit. There was a good bit

of leaves and other debris in my HVAC unit.



2. This next improvement has not been tested, but it should work.

Consider using a very small bolt and two nuts (one on each

end of the bolt) to replace the broken tab on any of those

white bushings. On my HVAC unit, I have two of these white

bushings where the tab has broken off each of them. The idea

is to drill a hole through the bushing, right through the center of

the bushing, oriented so that the head of the bolt serves as the

plastic tab that breaks off so easily. Use the nuts to secure the

bolt at either side of the bushing. This distributes the force of

the door stop across both sides of the bushing rather than

having the force build up on one side as Dodge did. I was lazy

and did not perform this improvement, rather I purchased new

white plastic bushings from Dodge. Actually, I did not think of

the improvement until after the truck was put back together.



3. The mode door from Dodge has the same design flaw where the servo

is able to twist the mode door shaft before it hits a stop.

This is what causes the door to break in the first place.

The mode door on my truck lasted 75K miles - not too bad for

an American vehicle. This twisting is what breaks the mode door

shaft thus necessitating repair. What needs to happen here is

the stop on the passenger side needs shimmed. Once the passenger side

stop is shimmed, the servo can no longer apply too much force to the

shaft of the mode door. You can glue some very small washers to the

passenger side stop to correct this. I used JB weld and some small

stainless washers (perhaps #4?). If you shim the stop too much the door

will not close completely.



Hope this helps anyone that tackles this job in the future.

 

[thashane]

Awesome post, thanks for the pictures!

 

[RVTRKN]

Just found this thread even though it is from 09/04/06 and have a few questions for you. My service manager says these trucks have fresh air as a permenant setting (about 20%) and that is why the 3rd gen trucks have a long cool down issue. Can you confirm that for me, and if it does, can you change it to completely to close off the fresh air?



I performed my own repair on my 2nd gen truck as well, but I also did all of the evacuation and recharging of the refrigerant myself, so I'm capable of doing this to my 3rd gen trucks as well if the dealer denies the repair because it doesn't meet the D/C requirements to authorize the repair.



EVERYBODY,

Side note on your own repair, don't make the mistake of letting your vacuum lines sag when you reinstall the HVAC control box or you will have to remove your dash again. I did not notice that and when I tightened the HVAC control box, I pinched the vacuum lines and only had defrost. I had to do the repair all over again except replacement of the evaporater which is why I had it apart in the first place. :{

 

[Briman]

Great Post, accolades to the author. It's a simple pleasure to have warm feet. I read the factory service manual for the instrument panel removal and found this one to be superior. The only thing that struck me in the factory read was "make sure you thread the parking brake rod thru the dash opening when pushing the dash back in place". My problem was caused mostly by two of the doors having sheared couplings. The tab on the outside of the coupling broke off and the coupling over rotated and sheared the notches on the inside of the door shaft. I like the idea another poster had to create your own stops with a small machine screw. After parts are no longer available this may be the preferred fix. One of the doors I had trouble with was the panel door. I will list the part number and price at the end of my post. I also intended to replace the blend doors but did not have all the parts when I did the job. On a Laramie it requires four doors (two on top the heater core and two on the bottom), two heater core housing halves (top and bottom) and four couplings. The housing half I had from the dealer had larger stops on it than the original one. The four couplings for the blend doors are all different. They are a lever instead of direct drive. Two of the couplings are linked by a metal rod on one side (passenger) and two are linked on the other side (driver). The only way to get the rod out is to cut a coupling lever. On reassembly you would insert the rod into the couplings and then push the coupling onto the door shaft. You will understand better when you see it. I guess all I'm trying to say is get all the parts before you start. You can always take back what you don't use.



05073963AA Panel Door (requires coupling 5019632AA) $28. 80

05073985AA Blend Door Laramie $34. 05

05073984AA Blend Door Laramie $34. 80

05161419aa Upper Blend Housing Laramie $64. 80

??????????? Lower Blend Housing

??????????? Upper Passenger Coupling Laramie

??????????? Upper Driver Coupling Laramie

??????????? Lower Passenger Coupling Laramie

??????????? Lower Driver Coupling Laramie



I'll get the missing part numbers from the dealer and edit this post in the next day or two.

 

[Sled Dog]

This post alone saved me $1000. 00 That will pay for a Life Time subscription to TDR.

 

[Prairie Dog]

Mine was done under warranty but I've had a buzz at idle deep inside the dash ever since. I can reach down from the passenger side and pull forward on the very bottom of the plenum and stop it. Any body have an idea of what may be loose or misaligned?

 

[DennyDay]

Great writeup - - - It needs to be published in TDR

 

[kuss]

Did something happen to the pictures?

 

[Bill Stockard]

Did something happen to the pictures?

I don't know what happened to the photos. Many of them were published in an article by Editor/Publisher Robert Patton in TDR Issue 79, page 42 and 43 which is available online if you don't have a copy of the magazine.



Bill

 

[Prairie Dog]

Ah this just plain sucks. We need the pics reinstated and the post made a sticky.

 

[kuss]

Thanks to Bill for reminding it was in Issue 79... although at least in the on-line version it starts on pg. 20.