HVAC Box Removal Air-flow Problems Fixed 98 GM Pickup

Sorry for the low light at some spots. I also really struggled to bring everything together and have it flow well, as this project was stretched out over about a month: working on it as I had time. I also in conjunction with this project replaced the entire ac system because there was a compressor failure. With the mileage on the truck I thought that would be better as opposed to flushing the components, and since I was needing to fix these issues with the HVAC box it was the perfect time to just remove it and replace the evaporator and make it much easier to do the other repairs on the HVAC box. I hope this video can be a help to someone. Produced with CyberLink PowerDirector 12

[@philipwilson9209]

Your video is awesome. I have my dash out and am struggling too much to get to the heater core and the evaporator coil. I saw the screws on the engine side of the fire wall and thought they might take the hole thing loose and started searching for a video showing how to do it. Your video is the only one that I found which shows it. Way to go.

[@calvinhenson4]

Note for everyone watching this.... I diagnosed the doors falling in by removing the lower vent shroud and looking up into the box. Clearly saw that one of the door fell in and the other is on the verge. I will be pulling my dash apart and revamping the entire HVAC just like in the video! Hope it goes well!

[@Dagrizzb]

Question: at 10:40 what is that red plastic thing attached to the top of your blower motor with the hot and ground wires attached to it?

[@RifeB6892]

I was able to get the flap back into place by just reaching up inside. No dash removal required. Found that out when I was replacing my heater core, I could access by taking off the bottom cover as you said.

[@willwalker5594]

Where’d you get the top part of the box with the doors in it

[@dano4572]

Would you do my 99 Tahoefor me!!!!!?????!

[@calvinhenson4]

@@dano4572 From what I remember about doing the job… PASS!

[@obslife1985]

I removed my whole dash and while I had it out I repaired the cracks and made my dash stronger and I also repaired the blend doors and made them seal a lot better because as old as these trucks are now the rubber around the blend doors are destroyed from the heat and if u repair them your dash will be throwing snow balls at u it just takes time and patients ….u can plastic weld your dash to repair the cracks then your dash won’t be rattling over every bump then get u a dash cover or a dash pad to help protect your dash from the heat/sun. I removed my HVAC without removing the evaporator and was able to replace the doors it just takes some time and patience

[@rgkaero4419]

God blessed me through you with this video. Thank you! Got mine out ( '98 GMC K2500 ) and back in resolving same issues. I could not fully open my doors in the space that I had to work in. Nor could I take the seat out. Praise God it's finished!

[@miggysudyka8477]

I'll admit I was very apprehensive about tackling this job, but with the help of this video I took it on and it was a success! No big deal. Thanks for helping!

[@timsorensen7350]

How long did the project take you? Did you replace the upper half of the box like this video shows or did you just take it apart and put the three new doors in it?

[@tomhenderson2430]

You did good. Saved me a ton of time finding those firewall bolts. We had an obstructed evaporator core, but we didn't know that going in. Thanks

[@tshepherd1091]

Was looking for a diagram online or layout of HVAC system to see what the issue could be, this video is thorough and detailed. It is much appreciated

[@DAYTONACRACKER76]

Need to do this soon thanks for such a detailed vid. Sure miss the days of manual controls

[@darrenwebb9312]

Thank You....finally a video for dash removal that shows where the bolts and screws are. All the other vids show the dash already hanging down with no clue as to how they got it down. I have a 1997 Chevy Silverado, upper case air distributor box has to be replaced, flap valve fell off. ( GM Part# 52467204 ) Again, thank you for posting this video...was at wits end trying to find a good how vid for this project.

[@65fstbk40]

To add to the last comment, the way I was able to get it done was by loosening and lowering the heater core and then removing the bolts that hole that portion together. Then I was able to pry the upper and lower sections apart about 1 1/2 inches. this allowed enough room to fit the mode control and the lower piece (the one with a single door) together and wiggle them into the two pieces that were spread 1 1/2 inches. There was enough movement to rotate the two door boxes forward and install the two rear clips. Ahh, I almost forgot, I also removed the 2 bolts near the centre of the firewall and loosened the 2 behind the overflow tank and the one thats accessed from the inside. My son gave me a hand and I think the whole job was about 8 hours. Hope this helps others.

[@snickerstorino]

never mind just saw this man ha ha, ignore my previous question thanks!

[@TheStangSlayer]

Dang I’d really like to pick your brain on this one. This job of pulling the whole dash and draining the AC sounds like a bear of a job on a ~30 year old dash

[@65fstbk40]

What kind of picking do you need.

[@utahyork3338]

That's a lot of work! Glad you replaced other parts since you had the HVAC box out. I'm thinking about doing mine now.

[@TheStangSlayer]

Thanks for sharing this! This helped me prep for a junkyard air box I’m about to pull and refurb for my truck.

[@helivesonforever]

Great job man. I'm doing the same thing because mine leaks water onto the floor everytime it rains through the fresh air intake seal. My airflow also comes out of every single vent no matter what mode I'm in. Tried replacing the control unit under the radio about 3 times now from various junkyards and that's not the problem. Has to be those doors that were broken in yours.

[@tylerpankratz5365]

Thanks a lot brother I just did mine and made a video as well for my problems. I gave you a shout out on how to take off the dash fully. I just needed to get to the vents and actuator so no full removal necessary.

[@wyattoneable]

Thanks for the steps. I've got a flow problem with my 98 and I will be digging into it soon. I hope I don't have to go as far as you did but we'll see.

[@rbear4576]

Make sure you price in the possibility of a replacement dash before you begin this journey. The late OBS vintage plastic is getting pretty brittle by now and there are no LMC reproduction dashes for 95+. Source: Technician broke my dash.

[@darkdelta]

Thanks looking for something else, hoping you would show it in passing, but no joy. However, a lotta good info here that I hope I WON'T need for a reference😁.😁😁

[@texasatrox]

What an excellent instructional video! Thanks!

[@garywilliams4855]

Awesome video! Thanks for posting. I did mine a year ago but did not replace part # 52467204 but thought I could repair mine. Big mistake. Now I get to do it all over again one year later. Thank you for the part info. I did not know that you could just order that part. I thought I had to buy the whole box. That was not in the budget. Thanks for a great video

[@MikeSmith-hx5xw]

Thank you for including the GM part #.

[@Shaft-Industries]

Wow! What a nightmare. That's about a $2,500.00 job at least.

[@brianhydrorenewal6632]

You worked your ass off guy, great job with this one! 💯

[@RifeB6892]

As far as fixing just fallen blend doors, try accessing from underneath first. I just got done doing a heater core and while I had my bad one out there was access to the blend doors from under the dash, my foot/face flap had also fallen like yours. I was able to just move it back into place by hand. Nothing else required. I’m not sure how long it will last but it’s working for now.

[@eastcoastken]

How long did it last?

[@RifeB6892]

Still working as far as I can tell, 6 months later.

[@65fstbk40]

yesterday I answered my question. I was able to get the mode control box changed without removing the entire HVAC system. It wasn't an easy chore but it can be done.

[@joelgalvan7075]

65 FSTBK I would like to change the flaps like shown in this video How do I do it without having to open the hole dash

[@geoff0brn]

You still had to pull the dash off I'm assuming? Where did you get the part for it?

[@calebschmidt2742]

How did you go about this? How did you change the top part with the flaps without removing the box?

[@65fstbk40]

@@calebschmidt2742 it was a long time ago now but I dropped the steering column as I remember and loosened the dash and tilted it to the rear which gave be some room between the windshield and dash. It was a bit of a struggle.

[@marksimpson5584]

Your video lives years later Still helping folks. Same problem upper center flapper door came out. Came out or did it loose a screw? This is mode door Actuator is on left of htr/ AC box driver side spring link Towards back& up of htr/ AC box. Flapper door is hanging.. Question is ..does a screw go in the end of rod that holds flapper Or a c-clip hold it in place? If you can member back than & if I Gave a good word pic of location.would you let me know how this is healed in place.(much thanks) Excellent video..

[@calebschmidt2742]

I have the same question. Did you figure out the answer to that?

[@kennycrews9553]

well put to gather video man nicely done

[@paul5276]

I've had the same problem with my 98 silverado for 3 years now. I'm going to do the same thing as you just did including the ac. was going to traid it in but changed my mind. don't want a payment.

[@domeniccaldarelli4443]

Oh my goodness! I was searching this because I didn’t think it was working properly/ blowing properly and I have heard that “gear noise” all the time and couldn’t figure it out!

[@PeteyG708]

Seems difficultly easy! Ha! Thanks for the video. It will come in handy!

[@reinaldogarcia5335]

Wow 👌 now that's 😳 the right way to do it..

[@normtheteacher5485]

Good job. Dont know if you still have your truck being video is 8 years old. If your blower ever goes out you may be able to fix it rather than replace it. I fixed mine by taking the motor apart and freeing up the brushes. They were stuck in their channels. Push on the back side with a sharp small file or screw driver. Hit the brushes with wd40 to loosen and lubricate. Push gently as the brushes crumble faily easy. Looks like they are made of graphite. Scratch up the armature while at it just enough to get shinny copper showing. Make sure the wire springs easily move the brushes in their channel. Lubicate the bushing that the blower shaft rotates in also. It does not rotate in a bearing. My blower works fine now except only on the Hi setting. Will have to investigate the resistor and or relay to fix that. At least I have heat now in the winter. Went all last winter with no heat while driving. That sucked.

[@calebschmidt2742]

What did you find out with the blower? Mine also only works on high. Was it the resistor?

[@normtheteacher5485]

@@calebschmidt2742 I haven't had a chance to dig into that yet because I am head over heals in another vehicle now. Im just glad I now have heat in the winter. I just run it on high and turn it off for a bit when my cab starts getting too hot. I have also rewired my windshield wipers. Same thing, they only run on fast. Strange, because when I had the wiper motor out and was testing it with a battery I detetmined what wires controled fast and slow. But when I put the motor back in the switch I had hooked up to slow speed activated the fluid squirt motor instead of slow speed on the wiper motor. I just shook my head and said I'll just be satisfied with the high speed when using the wipers. In The rewiring I have done, I have just used household wire and switches. Did this for my rear tail and brake lights also. I have a control panel that plugs into my cigarete lighter consisting of four houshold switches on a piece of plywood. This panel sits next to me in the seat. If I want to signal a left turn I just flip the left brake light on and off with my finger. If I am braking I just flip both left and right lights in the on position. For tail lights I just flip two other switches in the on position that are wired to the tail light filaments. The factory wiring is weird and I decided that as things go electrically wrong I will just rewire it my way. On the tail and brake lights, I just left the factory lights alone. The tail lights still work but brake lights stopped working. So I just installed add-on lights that this panel is wired to. Someday my ignition switch will fail. I bought a new ignition switch and gathered all the tools I need to change it out. I keep that tool kit in my truck for the day the switch fails. I have rehearsed changing that switch out a couple of times and know exactly what to do. Someday I'll probably be 500 miles from home and that switch will fail. With my tool kit and new switch with me I'll be back on the road in about an hour. Gives me a secure feeling.

[@calebschmidt2742]

@@normtheteacher5485 hahaha that’s awesome though with the turn signal! Whatever works. Hopefully I can get this blower to work in all settings- may try with the resistor replacement. Then thinking about also doing what this guy did and dropping the dash to replace those ac doors in the hvac box that have fallen out. It’s been over 100 degrees here for the past week straight and getting the ac figured out would be nice

[@eastcoastken]

​@@calebschmidt2742Did you ever get it fixed and if so what did you do? Thanks!

[@cltholen]

Do you have a list of all the parts you replaced? Not necessarily the part numbers...I can find those. Thanks!

[@gerardomendoza9688]

Sounds like a coffee ☕ maker

[@frankyeilding2546]

When installing the actuators don’t you have to be careful about their indexing? How did you do that?

[@owenbondar8925]

Lol 9:51 the impossible one i just finished replacing took me 10 minutes. I'm concerned about my mode doors blows out everywhere for me. Hopefully the flappers are still good in mine

[@Brian-ig8zx]

I don’t even have the time or the place to do this. I’m not sure what to do now. I had no clue I had to do all that. This sucks because I just bought the truck and have way to much money tied up in it to not fix it

[@steveracer8949]

Thanks for posting that video. Nicely done. I have a 96 that has the same problem with the ac/defrost doors and was wondering just how much was involved. with fixing them. Where did you get the new door assembly?

[@crosswayfilms654]

Sure. Glad I could be a help. I got it from gmpartsgiant. part # 52467204 It looks like the price went up since I got one. You might want to shop around a little.

[@OkieVet918]

my 1998 Silverado has the same issue, one of those flappers isn't in place anymore, just like yours. Can you replace that part without completely removing the unit? I know you went through the whole thing, but this is the only issue on mine, so I'm just curious. Thanks, great video!

[@abeldiaz6717]

where did you get the parts to repair the box.

[@blazestrawn7331]

This might no longer be relevant, but I found one on eBay under the description '1995-1998 SILVERADO SIERRA UPPER AIR DISTRIBUTION DUCT WITH VALVES NEW 52467204'

[@adamriggs8169]

Is there anyway to put that flapper for the defrost back into place? I have the same problem and don't want to take the whole thing apart

[@HarlanHarvey76]

Great job

[@ernesttrader7364]

Job well done

[@danb.3397]

It's the same unit for '88-'94 too. I'm doing mine now. NEVER want to do it again !

[@ooorah8499]

Hi Dan I have 1994 Chevy K1500 and the 52467203 has been discontinued, are you saying the mode control box 52467204 is the same and will work?

[@CarlJJones-zr9wv]

you should show how to hook up the linkage that's what i need everything else works

[@johnnymedina4013]

great video definitly help me get my air box out on my 1995 chevy c1500. I do have one question you replaced the whole pc that holds the defrost and director doors. Where did you get that whole assy because I would like to do the same and I'm having trouble finding them.

[@raidernation6810]

Can you put the flapper back in place? Or its junk? Currently have the exact same prob

[@micgregra]

Where did you get the replacement door box at.

[@scottm1317]

Is there any way to fix the flappers without taking the entire dashboard apart, or is it just a pain in the ass no matter which way you go about it?

[@bigsur175]

Where did you find all the parts, I have no heat right now

[@dano4572]

WHERE DID YOU GET THE DEFROSTER PART,,TOP LEFT SIDE OF THE MAIN BOX,,, THAT HOLDS THE TWO DIVERTER "DOORS INSTALLED IN IT????

[@crosswayfilms654]

I purchase most of the parts on ebay.

[@viccat6625]

Where did you get the part with the new flapper doors? Thx

[@45wesm]

Where did you get the new piece with the new flappers

[@terrylusk7612]

Where did you find the part with the 2 blend doors in it

[@Justin541998]

Mine is having the same problem. Thanks for the video

[@gushamilton5188]

Great video man. it works for the obs too. Thanks for this.

[@jacklandismcgowan1413]

Thanks for the disassembly video... starting on mine soon. How do you like that 7.4 ? I have access to a wrecked 98 3500 with a low mileage 7.4. My 98 k2500 has a 5.7 with 300,000 miles. I’m thinking about swapping in the 7.4. Thanks again for the video

[@ChristopherHastman]

What were the part numbers on the parts you used

[@65fstbk40]

I have the same question as Michael McClister. Can the mode doors be replaced without removing the whole works?

[@tedcarter3573]

Where did u get your parts. I'm getting ready to do the same thing.

[@blazestrawn7331]

I know I'm replying to a comment from 3 years ago, but I found one on eBay under the description '1995-1998 SILVERADO SIERRA UPPER AIR DISTRIBUTION DUCT WITH VALVES NEW 52467204'

[@user-ss6sy8yy2x]

where did you get the doors an the evaporator or the hole hvca

[@timothynerhus5025]

Great video. You had the defroster door in new box. I can only find the door only, Where did you get the box and door as a complete set?

[@blazestrawn7331]

I know I'm replying to a comment from 1 year ago, but I found one on eBay under the description '1995-1998 SILVERADO SIERRA UPPER AIR DISTRIBUTION DUCT WITH VALVES NEW 52467204'

[@km6344]

ughhh. i have the broken doors inside my box. the linkage pieces all fell off because of the doors dropping inside. i watched your video of sgowing the screws in engine compartment , then it cuts to you already having the whole box out! Okay, I'll figure how all that comes out on my own but then you get to the part where you have the doors that are broken off inside, and I'm really looking forward to how you got to them what made them fall if they needed to be replaced and how everything went back together and then your video cuts to where you have it already back together again it didn't show how the linkages went back on or anything! All the information I could have really used to watch you didn't add in the video! I don't want to see what you did I need to see how you did it! That's the purpose of the how to video! Sorry! I don't mean to sound ungrateful for your video but so many of these videos I try to watch for how to purposes and the part of the how to are missing! But at least I know how to take the box out I'll just have to figure everything out from there thanks for that anyway

[@65fstbk40]

I am about to change the mode control box. The thing with the two doors that have fallen out. My question is do you think I will be able to change it without taking the complete HVAC unit out. How does it split from the passenger side of the heater? I am hoping that if I get the two bolts out of the firewall and the clips remove I'll be able to....Great video by the way.

[@crosswayfilms654]

Yes, I think you can But the clips on the back side toward the firewall are very difficult to access. I think one guy said he was able to get them off, but not able to get them on when he put it back together so he just left them off and hoped it would be ok. My suggestion would be (if you have the dash laid down) to loosen the whole hvac unit from the firewall and you might be able to pull it away far enough to access those clips without having to disconnect the heater core and ac evaporator.

[@snickerstorino]

this is my exact same situation i'm going to have to live this weekend. were you able to get enough wiggle room by loosening the hvac unit? all i have to replace is that box as well but im not looking forward to this, how long did this take to repair?

[@Melody-ye7yk]

65 FSTBK where you bought it ? whats the name of that part so i can search for it ? the one with the 2 doors thing

[@Theferg1]

Great job bro. I ended up doing the same thing but my truck for some reason I cannot get the air to come out of the vents like it's supposed to it comes out but just very little. Would you have any suggestions? Thank you

[@Firewalker688]

Thank you so much for sharing this! I have found the part 52467204 but have a question for you. When on Amazon it says "also bought" the blend door as well. (They are calling it a valve). Did your box have both doors in it already? I don't want to buy them if they are already inside. I usually end up not returning them and have a shop full of extra stuff. Did you do the recirculation door while in there as well? Thanks in advance for your reply. Cheers

[@crosswayfilms654]

+Firewalker688 Yes the box comes as a unit with both doors installed. No, I did not do anything with the recirculation door. It was fine. Happy wrenching.

[@rippedimpala63]

@@crosswayfilms654 where did you order the boxe with the door I need it please help

[@marqueswilsonn]

Sounds like Led Zeppelin - Whole Lott’s Love

[@KCCLBTHORX]

So you were working on the lower actuator by your feet and that spring arm. Mine is flopping around loose and im installing the new actuator but cant figure out where the arm goes? You almost showed me where it goes then you flipped to removing the dash pieces. I need to know where that arm goes.

[@Isleepin516]

How is it air flow now??I think my account evap is clogged up

[@utahyork3338]

I'm assuming that when either (or both) flaps fall out, you cannot repair them and you need to buy new?

[@nickklein1894]

Where did you get all the parts from

[@cdogg1787]

Is there anyway to lock the blend door to recirculation mode only? I just got my A/C blowing cold but blend door is stuck I can hear the servo humming.

[@kevinmoss7057]

is it possible to replace just the flappers without taking everything apart?

[@muchgreatness7497]

Hi, 95 K1500 only blows hot air when of face setting. When I go from face setting to any other setting as the direction door is moving, the blend door opens and we're back to chilly air...Any idea why?

[@jimlommel5223]

Thank you very much for your video. My question is how do you re-assemble the part at the left side with the three doors back to the rest of the unit. I got out by brute force and now I have the new parts and can't figure out how to get it back together.

[@Austinole11]

Did you ever get it back together? Any tips?

[@jameslommel4602]

Yes I did but it wasn't pretty. To get it out, I am ashamed to say that I just took a pair of pliers and broke off enough of the right side housing to get it out and then to put it back together I used silicone sealer and applied it liberally around at the junction and then used a ratchet strap to hold them together until the sealant dried. Not pretty but it worked.

[@user-xl5np5dp8n]

Thanks for the video.

[@gointomexico]

How long did this job take you think?

[@benbriner9336]

How much was the replacement flaps and where did you order them. I'm dealing with the same problem

[@tedcarter3573]

Where did u get the new flapper. I'm sure that's not what it called but I don't c them online

[@blazestrawn7331]

I know I'm replying to a comment from 3 years ago, but I found one on eBay under the description '1995-1998 SILVERADO SIERRA UPPER AIR DISTRIBUTION DUCT WITH VALVES NEW 52467204'

[@satejano5206]

How did you determine he flaps fell off inside the housing? BTW, great video. thanks for doing it.

[@theobsessedguy3652]

I know this video is fairly old. But mine just wont switch to heat and i also have odd noises down there. Mine will still switch to whatever vents i want and to recirculate with no issue. What is my problem?

[@dakotavfl4926]

Was you having a restriction of air coming out the defroster my air comes out perfect everywhere except the defrost

[@rickr2029]

You really didn't remove the dash. Just removed what was necessary from underneath. I have this air flow problem also. I have a couple of questions. 1. Can this be done and completed on a weekend? 2. What parts would you have on hand, just in case? It seems like you could buy a new coil and if you do not need then return it. Thanks?

[@arthurhardy9130]

Where can find the blend door flapps , I’ve been trying to find them on the internet and can’t find them

[@benkanobe7500]

Where did you purchase the new flappers? Were they part of the top part you replaced or can they be purchased separately?

[@777gearhead]

WHERE DID YOU GET THE REPLACMENT DOOR ASSEMBLY? THX

[@kingbeav8386]

Where did you purchase the drivers side portion of the box with the doors in it? I accidentally broke my little piece off that the linkage attaches to and can't get it to glue back on.

[@donadams7469]

quick question for ya I have a 98 burban k1500 series that bugger that fresh intake door is half open vent blows hot managed to get the blower motor out for years we thought the system was just straight leaking so in the summer its all windows down is that fresh air inlet supposed to be half open when ac is running.... evaporator feels cold to the touch needless to say hot air was coming out of the vents and that was it clogged somewhere I would imagine

[@vincecastillo1973]

Can someone please help me. I need to replace all 3 actuators. I’ve found several but not sure which ones are right. I know 2 are the same and 1 other is different. If someone could help with the proper name or part number it would be greatly appreciated.

[@jaredmatherne366]

Did you ever get this figured out? I’m trying to replace all 3 actuators now and am not confident on which ones to get.

[@donniewright2673]

my 96 silverado only blows out top and bottom. I noticed the vent box was loose where the actuator sits. looks like it slides into place. if I join them together it blows out all the vents but it won't stay in place. any suggestions

[@kevingutierrez8006]

I know this might be a stretch could you tell me where you found your flappers

[@snickerstorino]

do you think i could possibly blow my evaporator out without disconnecting the lines from the accumulator? im having to pull the dash to replace the mode selector box because the doors fell in on mine and i was curious if it looked like i can split the main hvac box to shoot some air in there without having to pay someone to evac and recharge my system. just trying to get some better flow in the system as well while im at it

[@robbiemcgee2482]

For the case with the two doors on it; did you purchase the case with the doors already installed or did you purchase them seperatley? Could you please provide me a part number or tell me how i can find the assembly.

[@drdoutdoors1603]

Where did you buy the flapper doors and can I replace that without taking the entire dash off like you did. Everything on mine works fine except my flapper door has fallen down. Thanks

[@stevecarlson6462]

I sure do miss my 1971 Ford F250. My 1998 Chevy pickup is making that noise. My solution is to NEVER use the recirculating cabin air button again and let the little impossible to reach gizmo die with the fresh air flap in the on position. Recirculating the air is not important to me at all. In fact, it's kind of a stupid feature in my book.

[@jerrysmith6181]

I need to do this I have it all out but I can't find the parts...I need the top with the two doors in it

[@randenstevenson4041]

went and had my air system serviced and they managed to have it blowing cold and as hard as it will. he told me that i have missing vents and need to run new ducts. how do i go about doing this?

[@j-vibez5873]

Where did you find the mode door replacement box?

[@donadams7469]

heyo I have a burban I got both those actuators working for the defrost and hot air/cold air control which is right behind the glove box fan speed good heater core is not clogged rear vents work very well middle vents are ok but do you have any clue what to look for for the front outter dash vents by the doors there is almost no air coming from them at all and the fan is full throttle its also 90's

[@chitowncaddy]

did you do the orfice tube also? im looking to do my ac system on my 99 escalade nxt spring

[@crosswayfilms654]

+chitowncaddy yes I did.

[@benjaminmonterosa2349]

I wonder if it's the same for a 2003 Silverado

[@willbensmiller2413]

Where did you get the air box with the doors in it?

[@JM-yx1lm]

Ya but its a chevy so they always feel like a new truck !