Hi, I have just found out that a used 2003 GMC Sierra I purchased doesn't have a cabin filter. That is a big problem!!! I work in the country and dust is an issue. Does anyone know of a way to change/modify the airbox to add the filter??? TXS Chris

Here's the thread you need.
http://dieselplace.com/forum/showthread.php?t=5065
It may not be pretty but I believe it worked.

Just for some input...

I have a 2005 1500 Extended Cab. I installed the filters
in my truck.

I saw in the thread that everyone was concerned about a cover.

I cut the hole length 1/4 inch less than the filter and also
back from the front edge a quarter inch. The width of the hole
was wide enough to fit the filters without snagging them.

Had to angle the filter and bow it a bit to install.

First one went in, pushed it to the back. Fits snug like it is
seated in place with no wobble. Second one was installed the same
way and once in place, the corner edges sit on each side of the ledge
from the hole so it will not drop down unless you grab and pull.

For a cover... I used a couple of strips of the old reliable duct tape.
Reasoning is.. filter is in place, just want to make sure hole is sealed,
easily removeable when time to change filters, not a cosmetic issue
because there is the plastic kick plate/cover that hides the whole
fan assembly.

:grd:
4wheeln

What'd you cut the hole with? Got pix?
Thanks,
Lar

Your dealer can order you a cover for the hole for a few bucks. Cut the hole with a Dremel. They build the air conditioning units where I work.

Hey slip one out in your lunch box, like Johnny Cash's song, "One piece at a time." ;) Just kidding, are there scored lines or some guide where to cut, pix maybe? I don't recall on my '01 where exactly the slot was.
Thanks.
Gup

Guppy,

See the link in post #2. Pics on second page.

Thanks Bac, missed that link.

No prob, Guppy. You thinking of cutting into your truck? I'd like to have the filters too, but I'm not experienced enough with a dremel to try it.

Especially now w/ your HANDicap. You get one of those little blue parking passes?):h ):h

That is too kewl! On to my next project! I will do the wifes Yukon XL too!!! Thanks Desert Diesel for the link!!!

Oh boy, another convert! My dad put the filters in his 03 Dmax. Carving up his new truck probably caused him some concern but they are in and ready to keep the interior dust free. He found crap & corruption in the duct when he opened it up, leaves & stuff. Dust free interior even with the vent open - - - I'll never figure out why GM dropped that idea!

Now....who wants to go out to their '02 and measure the slots in the ductwork for me? I think from looking at the pics that the slots run up about 2 inches and back about 4 inches.

Hey Tom...I see a "work on our trucks" day coming up soon!:cool2:

Heh Heh Heh.....I see beer in our future......:lol:

Now....who wants to go out to their '02 and measure the slots in the ductwork for me? I think from looking at the pics that the slots run up about 2 inches and back about 4 inches.

Lemme see what I can do about a detailed picture..............

:cool:
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I don't have the pics of the actual cutting procedures but you should get an idea of the project. The length of the hole in this case is about 1/4" narrower than the filters, but its and easy squeeze to fit the filters in place. First one in, slide it towards the firewall, next one is held in place by the "shoulder" on the front of the duct. BTW, the screw over the transmission hump is a real pain to get to. In this case a 9/32, (7mm) 1/4" drive with a very short extension is the best. Sorry for the delay with the pics. Hope this helps.

8 pic limit.... now for the finale

Thanks Mitch, now I have a weekend project!

Its not much, maybe about an hour.

--- applause --- Thanks Mitch! NICE clean install! ---applause---

I guess Jeff (Crazy Daze) and I definitely have to get together and have an install bash at his place! I've got two '02 filter housing covers coming from GM next week. Going to see if they retrofit onto the '03 housing....that would allow for cutting the full hole for the filters.

Would you recommend sticking a vacuum hose into that hole and cleaning the duct out as best you can first? Also, would you think the first filter replacement should be relatively soon after (like a couple months) to allow the system to get cleaned out?

Ya buddy, clean out the duct first, and each time you replace the filters. but this way you have a "trap" for the crap. As far as early replacement, just check it in about 6 months. My first replacement, I just washed the filters with dishwashing liquid and dried them, then momma wanted some phoo-phoo sprayed on them (ya buddy!). We did but it was gone in a day or two.

Yes the covers for an '02 will fit '03 - '05 trucks. The mounting is the same.

Great pics Mitch!!! I can see in your pics right where they filled in the actual opening.

Tom...we just cut along those lines and then install the filters and the cover, it'll look like an '01-'02 filter housing.

I can't thank ya enuff Mitch! Those are some very informative pictures. And some great hints. I think I'm going to try and do the whole job without completely removing the inner screw.

If you have a dremel, especially if you have the right angle drive for one, use the cutting wheels. suggest you use a face shield cuz the hot plastic burns like a by gawd when its your skin! If your hole is a little ragged or out of size a tad, use a rasp to clean it up.

accrash -- thanks for the tip! It'll be a very clean install then!

Jeff -- You're right. Should be a nice, easy install! :muahaha: When do you want to get together? I figure the covers to be in on Tuesday. What kind of beer do you want to drink?

Mitch -- Thanks again for all the info.

accrash -- thanks for the tip! It'll be a very clean install then!

Jeff -- You're right. Should be a nice, easy install! :muahaha: When do you want to get together? I figure the covers to be in on Tuesday. What kind of beer do you want to drink?

Mitch -- Thanks again for all the info.

Tom...I have to order the filters. I should be able to pick the filters up from SPO on Tuesday. Then let me chat with my babysitter so I'll have someone here to watch my daughter while we do this!!! I'll call ya over the weekend.

I'm too psyched! I really like the expensive Irish import beers, but Bud Light works just the same!:grd:

This should work out :cool2: too, as one can photograph while the other works and we can get a fully accounted and photographed cutting and installation with the OEM cover.

This should work out :cool2: too, as one can photograph while the other works and we can get a fully accounted and photographed cutting and installation with the OEM cover.

All this delegation of job roles, but I don't see who has the most important role of opening the bottles of refreshments!

By the way, Honey Brown is the beer of choice for me! :muahaha:

All this delegation of job roles, but I don't see who has the most important role of opening the bottles of refreshments!

By the way, Honey Brown is the beer of choice for me! :muahaha:

Hmmm....the man has a point there....

Hmmm....the man has a point there....

Well...since we both have a bad hand, we'll have to make sure we have pop top cans.:lol:

But your 3 year old wants to help, right? Maybe the babysitter can be "beergirl" too?

:lol: Either that or we have to work together!

:thumb: :clap: Now that's the best idea I've heard yet! My wife won't like the fact I'm turning our beautiful little girl into a grease monkey, but at least I'll know I have a girl who can hold her own at the dealer service counter.

You guys have me curious now... My truck has been garaged it's whole 6800 mile life, guess I'll be doing this mod wile I still have a dust free system. Thanks for the step-by-step pics Mitchagain. :ro)

TheBac & CrazyDaze, be sure to post the pics of your filter doors installed. That's how I'd like to do my mod... The masking tape would work, but would get messy after a few changes.

D3...Will do! It should look just like the 01-02's when we're done. The cover and filters are so cheap from GM that I'm surprised they stopped installing these. They spent more money changing the molds to eliminate the openings....

I work at the plant where the HVAC units are built. According to our "engineers", the reason they were discontinued is GM was having alot of problems with owners not changing the filters, then bringing the vehicle in for service with complaints about the blower motor not working properly. These same owners would then become irate when they found out this was a maintenance item and therefore, not covered under warranty. Personally, I'm glad they at least left the option there for us to install them ourselves. For those that are not mechanically inclined, the dealer will be happy to install the filters for you, for an exhorbitant fee, of course.

Hey ac...I figured that was the case about why they elimanated them. But as easy as it looks to cut the hole and install these, I'll pass on the dealer! Shoot...I pass on the dealer just about all the time!!!:muahaha:

I had a 2000 and changed the filters at about a year. They were nasty. After I got my 03 and found out that they didn't have filters I couldn't hardly beleive it. I asked a question in here about the dust and dirt and crude and someone told me thats what nose hair is for!! Well lately I have been getting a stale smell in my truck. Wondering what to do I looked here and found what you guys were doing. Sounds good. I hate cutting into something I don't know anything about. If you keep us posted and keep showing good pics like you've been doing maybe I'll find the nerve to try it.
Thanks
Billy

I work at the plant where the HVAC units are built. According to our "engineers", the reason they were discontinued is GM was having alot of problems with owners not changing the filters, then bringing the vehicle in for service with complaints about the blower motor not working properly. These same owners would then become irate when they found out this was a maintenance item and therefore, not covered under warranty. Personally, I'm glad they at least left the option there for us to install them ourselves. For those that are not mechanically inclined, the dealer will be happy to install the filters for you, for an exhorbitant fee, of course.

Why didn't the engineers install a pressure differential switch or gauge (like the one on the air filter or a sensor wired to the DIC saying "change havac filter")? They could have at least made the changeable havac air filter an option... I would have bought it.

TheBac, you got the part number for the filters?

TheBac, you got the part number for the filters?

Lets see....Cabin filter part numbers:

GMPartsDirect -- 52485513 -- $15.50 (retail $25.89)
AutoZone ------ CAF1707 --- $19.99
NAPA ---------- FIL4805 --- $16.99

I'm thinking these prices have to be for a set of two filters, as needed.

Thanks!

Will my wife's 2001 Tahoe have this? If no one else posts pictures, I can get some of my wife's truck.

Will my wife's 2001 Tahoe have this? If no one else posts pictures, I can get some of my wife's truck.

D3...yes, your wife's Tahoe should have them! '01 & '02 GM trucks have them.

Crazy & TheBac - - -

Well? How went the weekend project? Or was it just a refreshment filled weekend?

Planned for Wednesday. Have to wait for the covers and filters. Looks like great weather coming in too..

"Crazy and TheBac" sounds like a '70s sitcom.....:lol:

Tom, that tis one fine avitar! No wonder you are an agent for the Big Brown Delivery!

TheBac and CrazyDaze
I ordered my cover today.
Keep us us up to date.

Thanks
Billy

Well today being Wednesday and wondering how TheBac and CrazyDaze project was going to go!! I had a little time this morning so I thought I would pull the kick panel off. I first droped a socket under the console and then broke off a tab that holds the trim on the side of the console trying to get the socket ( should have let it stay there ). Still don't have the screw out. If I do get it out I'm thinking that it might not go back in. (That will bug though)
Hope you fellows project goes much better.
Hope to get a report.:help:
Billy

My dad lost 2 or 3 sockets and "special" tools behind that console cover! Long magnet and a mirror after he got the cover off was his solution. He did cuss a lot too, though it probably had no effect.

The solution....DON'T TAKE THE COVER COMPLETELY OFF! You really don't even need to loosen that screw. I found that out....you will kick yourself if you remove it, esp if you have a center console.

UPDATE: The latest episode of the "Crazy Daze and TheBac" show:

Jeff's a heck of a nice guy! His truck is very nice! You should see his boat...:muahaha:

I got back home about 8PM, got the pics Jeff took, have to take some of my truck.

We found that there is a very big difference in the HVAC ducting between our trucks. I need to call ACCRASH and ask him some questions. The cover I bought DID NOT WORK! Darn it! I've got to go back to the dealer...

Will post what we did tomorrow guys!

I'm thinking of using some 1/8" aluminum or steel and make a couple covers. Will let you all know how it goes...

:) Thanks for the compliments Tom!!! And it was great getting meet you and tackling a little project on the trucks.

Guys and Gals...this project is not as easy as it looks. You really have to take great care while doing the cutting. As you'll see by the pics that Tom will post tomorrow, I really Censored mine up. Not totally, but I made the opening too wide. I don't know what I was thinking when I was cutting.

But Tom is going to fabricate some covers and I'm sure he'll come up with a very workable cover.

So...the saga continues....):h

Well my weekend project turned into a mid-week project. Took longer to get that Censored hump screw in than the whole hole cutting. I'll never remove that screw again. I use a pneumatic "Dremel" tool, It's alot easier than electric. Sounds like a dentist's drill! Here's the pix. I decided to use metallic duct tape to seal.

Biggest thing to remember with the "hump screw" is to put some tape on the inside of the cover plate over the screw hole, then poke the screw through the tape to hold it in place. Works like a charm.

Never thought of trying to cut the hole without removing the cover. Looked like it might have been a contortionist's nightmare!

Biggest thing to remember with the "hump screw" is to put some tape on the inside of the cover plate over the screw hole, then poke the screw through the tape to hold it in place. Works like a charm.

Never thought of trying to cut the hole without removing the cover. Looked like it might have been a contortionist's nightmare!

I left my hump screw tight, never touched it. I just removed the other two outer screws and rotated the kick plate down and away. Tom totally removed his. I don't think it was any different with it totally removed or still there, when it comes to cutting anyway.

Tom's going to fill everyone in later today, so I won't comment too much on this.

If I have time...

ON EDIT: I'm tired. Had too long a day to sit here and type up a report with pics at 10PM.

I'll get to it tomorrow. I made a cover out of 1/8" aluminum and common household foam seal. Worked perfect.

Tom, if you're going to sell covers, count me in for one.

Biggest thing to remember with the "hump screw" is to put some tape on the inside of the cover plate over the screw hole, then poke the screw through the tape to hold it in place. Works like a charm.

Never thought of trying to cut the hole without removing the cover. Looked like it might have been a contortionist's nightmare!

Yea, Mitch, I tried that, didn't work. There was too mush lateral movement in the screw slot. Besides sticking the cowling w/ taped screw kept knocking the screw outa alignment loweron ducting plactic. I think the engineer who designed that should have HER lips sewn shut, vertical, not horizontal, to keep any of her offspring from screwing-up something else down the road!:rant:

This afternoon I got the Dremel out and sawed up an old sheetrock mud bucket. I think I'm about ready. Well maybe in the morning I should trying sawing up one standing on my head with one eye closed. And then I might be just about ready. Thanks for all the hard work and especially keeping us informed.
Billy

Sorry about the wait, guys.

When removing the kickplate cover over the HVAC unit, DON'T remove that screw over the tranny hump! If you have a center console, you will end up cursing out the engineer that designed it! I took my cover off, while Jeff left his attached. He was the smarter person. After fighting with it for 15 minutes, I ended up leaving that screw out, pending me thinking up an alternative way to fasten it.

**Jeff and I found that the filter access areas on our 2003 GMC's were DIFFERENT! Mine was a blank, flat area about 11 inches long, and while his was also that long, it also went up the side of the HVAC unit about 3 inches. On Jeff's, it almost seems like the opening is scribed into the plastic, too. **
We both think it could be because he has the manual climate controls, and I have auto. There must be some physical changes in the HVAC ducting to go with the different controls. It may also be to help facillitate the filter install/removal, since I found later while trying to install my filters that the they don't quite want to go straight in because of the floor board. The additional 3 inches up the side made the filter install on Jeff's truck a breeze.

The first pic is of my HVAC, the second is Jeff's. Notice the screw boss on mine. The boss on Jeff's is just out of the picture, up at the top of the scribed area. I guess GM left them there to secure future filter covers if someone wanted them.

Cutting the holes is easy with a dremel. We used a fiber cutting wheel attachment. Don't use the "drill bit" type blade unless you have extremely steady hands and a boatload of guts. GO SLOW! One wrong move and you will have an unwanted leak!

Jeff did his first, and cut up the side of the box about 3" and then along the bottom 5.5". He originally stayed about 1/16" inside the scribed lines in the plastic, but then widened the hole out to the edge of the scribe marks along the bottom. You can see the scribe lines and the extra width in the picture of his cut out in pic#5. The bottom slot ended up being 1 1/4" wide. We found later that this may have been a bit TOO wide. So, lesson learned....stay about 1/16" inside the scribe marks, and don't cut past them. If, while trying to install the filters, you find that the opening is still not wide enough, use your dremel to carefully shave the sides of the slot. I figure its a hell of a lot better to shave some material off later than curse yourself for taking too much in the first place.

Learning from this, and since I didn't have the ready-made scribes, I marked my opening 6" long by 1 1/16" wide. I started the slot about 1/8" in from the front corner of the boss. I also left about 1/16" on the sides of the opening for sealing later. I may make the slot about 3 inches longer at a later date, to facillitate the filter install/removal.

Notice the wonderful blue cast! I'm getting pretty good at using just my fingers! Also, we didn't have the flexible dremel attachment. We both had to unplug the small wiring harness to that "box" right next to the opening to allow a straight-shot cut. See pic #1 for the harness location.

We used a razor blade to clean up the corners of the slots and to trim excess cuttings away from the slot sides.

Use a vacuum to clear any debris from inside the HVAC unit, and to clean up the plastic debris from the cut.

Since Jeff cut his slots wide, his filters went in very easy. Just install the first one (long-dimension up), and push it back into the HVAC housing as far as it can go. Then install the other filter right next to the first. No matter which housing you have, the filters are a tight squeeze. They do not have a solid edge, so they like to grab each other and not slide past easily. My housing was trickier. Because I cut my slot smaller, the filters rubbed the sides of the housing going in. I also had to twist my filters slightly to install them, and hold the first one in place so the second didn't crunch it while I pushed #2 up into the housing. My trials installing the filters are what got Jeff and I wondering if GM changed the housing design to help the install. I may have just got one of the "old" design ones left over from '02.

The GM filter covers we both bought were COMPLETELY wrong for our applications. If you'll notice, I had the moderators take the cover part numbers out of my previous post. I don't want you guys wasting your money on incorrect parts...
Jeff found that, since his slot was wider, he got some air leakage from around the filters. The filters also help seal the opening. Because I cut mine slightly thinner, I had very little leakage with mine. We both used tape to temporarily cover the holes until we could find or make the proper covers. The tape sealed the leaks temporarily. The Install -- Part 2 will detail the cover I made for my filter housing.

Tom, what tool did you use on the dremmel to cut that? Was it the little circular saw blade?

Since the covers Jeff and I bought were incorrect, I figured I'd have to make something to cover the filter opening and seal the HVAC unit. We both figured that tape was just temporary.

My cover was simple to make. Since there is a slot at the firewall end of the opening thats the same width as the opening, I figured I could just slide something into that, and secure it using the screw boss on the front.

So, I went to Lowe's and bought a piece of aluminum 3 foot long x 1 1/4" wide x 1/8" thick. You guys should have seen me grin when I saw they had that width...:D. No extra cutting needed! I was thinking "Damn, buying the materials will take longer than making it."

I cut off a piece 11 3/4" long, and drilled a 1/8" hole in one end, centered, 1/4" from the end.

I then added 3/8" wide by 3/16" thick foam seal tape around the cover edges.
I had also found 1 1/4" wide x 3/16" thick seal at Lowe's. This would seal the entire filter cover, but I was unsure if that would hinder tightening the cover down. After installing the cover, I realized I was wrong, so when I change out filters again. I'll change that seal.

Notice in the pics how I did not run the seal all the way to the ends. I left about 1/4" on the "slot" end, and about 1/2" on the "screw" end.

Just slide the cover into the slot, and secure it with a 1/2" #6 screw. The 3/16" foam compresses just enough to seal the opening, but did not hinder the cover while tightening it down.

The filter opening is now covered, with NO air leakage.

Now Jeff's cover is going to be MUCH more involved. It will have multiple bends, PLUS a blind hook in the back. It's going to take me a bit to fab something up for his truck. I will post about this in Part 3 when I get it done.

So now we both have cabin filters. It's a very simple modification. It is easy to do, you just have to be careful when cutting the slot for the filters.

Sent you a PM Timberwolf.

Thanks for the question. I added that info back into the Part 1 post.

Tom
Outstanding!
I'm ready to try it now. You have made simple for the rest of us.
Many Thanks
Billy

Looks awesome...........

Do a detailed write-up and post it so a MOD can move it to the DYI forum........

Nice work.........

THE BAC MOD..............:cool:
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Those two posts arent detailed enough? :lol: Dang, I'm slipping...

I've got to try to make Jeff's cover first.

But seriously..I'm not going to take credit for this...someone else started it a while back...I just posted what we did.

My HVAC is just like yours Tom. This afternoon I cut the hole. That went real good. My problem came when I put the filters in. I got my filters at NAPA. I ones I got have ( HAD ) foam tape with some kind of cloth on the foam. First one went in just fine the second not so good. It wouldn't slide by the first one. After a few tries they are both trashed now. I think I'll try a set from Auto Zone. Made a cover from plexiglass, don't like it (some I had laying around). I'll get a piece of aluminum to night when I go to get the filters. I just don't understand why I couldn't get the filters in. Maybe I
shouldn't have celebrated after I got the hole cut, I guess I should have put the filters in and THEN had a beer or 2. I think tonight is a beer or SIX night.

Nice Job TheBac and CrazyDaze

Billy

I had no idea there would be any difference between the Cheby & the Jimmy. You guys did a great job, kinda makes the duct tape look a little like 'hicks from da stix'!!

Tom, after you got the cover plate made did you cut your hole back towards the firewall some more? Hard to tell with the seal on the aluminum plate (last pic this page).

Congrats on the fine job!

My HVAC is just like yours Tom. This afternoon I cut the hole. That went real good. My problem came when I put the filters in. I got my filters at NAPA. I ones I got have ( HAD ) foam tape with some kind of cloth on the foam. First one went in just fine the second not so good. It wouldn't slide by the first one. After a few tries they are both trashed now. I think I'll try a set from Auto Zone.

Billy

Billy, Sorry that your filters got crunched. I posted that the filters are tough to get in, I will have to clarify that, I guess.


Since Jeff cut his slots wide, his filters went in very easy. Just install the first one (long-dimension up), and push it back into the HVAC housing as far as it can go. Then install the other filter right next to the first. No matter which housing you have, the filters are a tight squeeze. They do not have a solid edge, so they like to grab each other and not slide past easily. My housing was trickier. Because I cut my slot smaller, the filters rubbed the sides of the housing going in. I also had to twist my filters slightly to install them, and hold the first one in place so the second didn't crunch it while I pushed #2 up into the housing.


As for the cover, plexi is too flexible, and wont stay straight under load. You'll get a bend in the middle.

I had no idea there would be any difference between the Cheby & the Jimmy. You guys did a great job, kinda makes the duct tape look a little like 'hicks from da stix'!!

Tom, after you got the cover plate made did you cut your hole back towards the firewall some more? Hard to tell with the seal on the aluminum plate (last pic this page).

Congrats on the fine job!

Mitch...Jeff and I both had GMC's. The Chevy and GMC should be the same. He is on the trail of the reason his was different. If the hole you're refering to is the slot toward the firewall...no, I did not cut it out any. The aluminum strip fits perfectly into it. The hole is actually about 3/16" tall, but if you use a piece of 3/16" stock for the cover, the seal won't have any room to fit and compress, and the cover will actually bow down.

Hey Bac, did UPS girl keep your liquid refreshments coming so you wouldn't get dehydrated? ;) I did mine at 102* with the sun shining in the windshield. Hot MoFo!!! :( I also noticed quite a bit of muddy mung on the fins. Wiped it off as best I could. Guess I waited too long to install. Does anybody know a way to clean the fins?

Um, no...UPS girl did not bring refreshments. Jeff did....I owe him beers now....:thumb:

As for the gunk, my AC fins had wet gunk all over them too. I wrapped a towel over a ruler and CAREFULLY wiped it off as best I could. I figure it was all wet because I had just washed B.B.T. earlier in the day. It must be those dusty Texas roads....

How much trouble would it be to replace the complete plastic HVAC duct under the dash with a 2001 or 2002 duct with the filters. Just Asking!

How much trouble would it be to replace the complete plastic HVAC duct under the dash with a 2001 or 2002 duct with the filters. Just Asking!

*shudder* I don't even want to think about that... *shudder*

I think that would entail removing the entire dash.

*shudder* I don't even want to think about that... *shudder*

I think that would entail removing the entire dash.

And Then Some!!!

Tom I remember you saying they were a pain to get in. I think my main problem was that I got a little impatient. I got more filters from Auto Zone and they look like they are a much better quality than the Napa ones. I might also will do like you said and cut the sloy a little longer. I thought that plexiglass might be to flexible and it sure is. Just thought I would try it (wasted time). Got a piece of aluminum tonight. Try again tomorrow. I thought you did an excellent job detailing the job.

Well...I just got home from vacation and wanted to make a note of a few of the observations I made after the filter installation.

(1) The air smells better while traveling down the road.

(2) In conjunction with (1), I don't have to travel with the recirc on as the air smells much better in traffic. But I have always had the recirc on because the air wasn't cold enough. Now I have so much cold air that I not only turn off the recirc, I am turning the temp up slightly with the fan still on 2 to keep air moving.

Makes you go "Hmmmmmm", and wonder if the A/C not working properly on the '03 and up trucks is due to too much hot air flow across the cooling unit in the dash (evaporator or condensor, I can't remember :-)) with the filters being deleted from the system.

I was disappointed also when I saw my new '05 did not have the cabin filters. Looking at the duct housing, it looked the same as my '02, except without the access panel.
So.........I cut an access panel in the same place as my '02 and the stock filters fit right in place. I got a piece of 1 1/4" wide 1/8" thick aluminum flat bar and made my access panel cover. Installed two self tapping screws (one each end of the cover) and it works great. Now I have cabin filters again.

I am hopeful that someone can adapt or make a charcoal filter, that will eliminate a lot of the odors that get thru with the recirculate off and would be a more effecient filter than just paper........

HMMMMMMMMMMM ????????????????
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I am hopeful that someone can adapt or make a charcoal filter, that will eliminate a lot of the odors that get thru with the recirculate off and would be a more effecient filter than just paper........

HMMMMMMMMMMM ????????????????
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I bought some cabin air filters at NAPA in Maryland and they were carbon! I think they were:

Fram CF8791 Cabin Filters

I bought some cabin air filters at NAPA in Maryland and they were carbon! I think they were:

Fram CF8791 Cabin Filters
It looks like it might have Carbon?????????

The BOSCH #C3730 is $40.00 at rockauto.com and states it has activated charcoal filtering...........

Ask scott, I'm sure he would know.

Do you need to use 2 of those Bosch filters?

Do you need to use 2 of those Bosch filters?

Yep, the filters come 2 to a box and you remove 2 and replace 2.

Okay, charcoal - the ones I got looked just like the photo of the Bosch one. I have NAPA #4805 in there now, no charcoal, lily white paper.

Cool I was thinking they were $40 ea

Sorry this took so long.

Jeff's HVAC cover was very intricate. It couldn't be as simple as my flat piece of aluminum, now could it? :lol:
There are multiple bends involved, along with the tab to go in the hidden "slot" up near the firewall (this acts as the rear support). I fabbed the original one thats currently in Jeff's truck out of 1/8"T x 1 1/4"W aluminum. This would have sufficed in most normal applications, but unfortunately, we had made the slots for the filters in his truck too wide, and even with a thick foam seal, the cover just didn't seal right.

The cover in the pics is the newest version. I made it out of 1/8"T x 1 1/2"W steel. The steel took the bends better than the aluminum did. I also shortened up the length and height by a smidge to cut down on the "slop" in the seal area that I didn't like from the first incarnation. The only trouble I see is going to be the cover's weight...it's probably double that of the aluminum. We'll see.

I just have to get Jeff over to the house again in order to drill the anchor screw hole in the right place, and do the final fit. I will add 3/16" foam seal around the perimeter of the cover, including extra in the corner to assist with seal and fit. It should be a simple install. But you guys all know about "simple". I'll post dimensions and install pics after I get this cover fit correctly.

1) The 03-up manual HVAC units are not the same design as the 03-up auto HVAC units. Jeff's in a manual one, mine is auto. The filter bosses are different, and the covers are different. NEITHER is very close in design to the 01-02 units, too.

2) When cutting your slots for your filters, DO NOT cut them more than 1" wide. This will give you a little bit of leeway when you are cleaning up the slots with a razor blade or file. I highly recommend you DO NOT let the slots get any larger than 1 1/8" wide! The slot lengths aren't as critical...I figured 6" was about right to fit the filters in. I do not recommend cutting the entire length of the boss, though. If you go over 1 1/8" wide, the covers will not seal as well.

3) I got to thinking about this after almost butchering both the filters as I was installing the second one. The filters do not have smooth sides, and they fit very very snug in the HVAC unit. As you install the second filter, it will catch on the first, and both will "crush". bsiler found this out the hard way. Sorry, man. To avert this, hold a thin piece of cardboard (and I mean thin) as wide as the edge of the filters (and about 12 inches long) in between them as you insert filter #2, the second filter should slide right in. Then you can remove the cardboard, and the filters will seal just like they should.

4) Jeff noticed that his A/C seems to work better, and is way colder. He surmised that the HVAC units were originally designed to HAVE filters (hence the blanks where the slots should have been), and the airflow and air volumes were designed in with the assumption that filters and their restriction would be present. GM did not redesign the HVAC units after the filter deletion, so an excess of outside air was being let in and run through the heater core. This extra airflow made the A/C have to work that much harder, and since it had to overcome the extra heat in the incoming air it couldn't keep up. Therefore A/C efficiency was lost. Now that the filters are in the way of the heater core and restricting the airflow past it, the A/C is being allowed to work the way it was designed to.

So when will these be ready to purchase? Looks pretty sweet!:ro) :ro) :ro)

So when will these be ready to purchase? Looks pretty sweet!:ro) :ro) :ro)

:lol: ...I said the same thing to him after he fabricated and installed the first cover on mine.

Tom...I'm still working on the camper dealer. Shooting for Wednesday.

:lol: ...I said the same thing to him after he fabricated and installed the first cover on mine.

Tom...I'm still working on the camper dealer. Shooting for Wednesday.

Thanks for the compliment, Jeff, but it's too expensive to build and sell them at the present time. Maybe in the future. I can't fab them all exactly the same because I don't own that kind of metal smithing equipment. You saw what I have -- a vise, grinder and a BFH.
I can get 2 of your cover and 3 of mine out of a 36" piece of stock. Figuring in fab time and paint, each cover similar to yours would be about $10-15 bucks. The ones like mine would be about $8-10. I don't think it would be too popular at those prices.

$20 would be fine with me all crap a side. I hate the dust and smell when going mud riding.......:grd:

$20 would be fine with me all crap a side. I hate the dust and smell when going mud riding.......:grd:

Ditto ...and a template to use to cut the slot :)

Thanks for the compliments guys. I'll mull it over.

Thanks for the compliments guys. I'll mull it over.

Ha ha ha.....he said mullit.....:D

Tom there is a thread for that....;)

:funnypost I thought that too.....:lol: I wondered who'd catch it.

Did you even have to wonder......;)

Here are a couple pics of the cover mounted in Jeff's truck. It fit almost perfectly, and the seal was spot-on. No more air leaks! About the only thing I could change was making the "tab" end about a 1/16" shorter.

I want one!!!!!:help: :help: :help:

Tom,

Seriously, you should really consider making these (covers) for your fellow Dmax brothers that want to do this mod.
I do realize it's a lot of work, but you've got the time, expertise, and the love of your fellow brothers out here!! ;)
I know I can speak for all of us when I say we would really appreciate very much. Think about.......and put me first on your list. :D

I'm thinking about it. I PM'd Nick about what a "limited vendor" is.

I talked to a metal shop on the route yesterday, they can get me aluminum that will take 90* bends better than the stuff I was using. It was too brittle, thats why I made Jeff's out of steel. But to do it right, I'll need some kind of brake setup to do the bends.
It'll take me a bit to come up with a template setup for both styles of HVAC. Then I have to come up with directions, what all to include, etc....

I was thinking that making a "kit" including the NAPA charcoal filters would be a good idea.

Give me a couple weeks to see if this is all possible. PM me with your ideas....

Well, You would for sure have the shipping problems taken care of Huh!!
;)

Tom and I are doing some research on this project....After this weekend, we should know a bit more :)

I WANT ONE!!!!!!! LET ME KNOW I WILL PAY YOU AS SOON AS POSSIBLE.......:ro) :ro) :ro) :ro)

I need a few people with 04s and 05s with both manual and auto A/C to do me a favor. Can you lower the black cover below the glovebox and check what the HVAC area looks like? I'm betting GM didn't change the HVAC ducting, but I have to make sure first.


Tell me if the area looks like one of the two pics below.

http://dieselplace.com/forum/attachment.php?attachmentid=7963&stc=1&thumb=1&d=1125066382 This is the filter area for those with Auto A/C. Notice the little "nub" for the screw is right even with the filter boss?

http://dieselplace.com/forum/attachment.php?attachmentid=7964&stc=1&thumb=1&d=1125066382 This is the filter area for those with Manual A/C. The little "nub" for the screw will be just above the "scribed" area and even with the lower metal dash brace under the glovebox.

L

And I PM'd you Tom.............................................

Mine is a manual unit and it's an 04 LB7 looks like this

http://dieselplace.com/forum/attachment.php?attachmentid=7963&stc=1&thumb=1&d=1125066382

Hey Bac since mine is the manual unit and it looks like the first one that is an auto I bet the diference is between truck plants and not if it's a manual or auto ac unit. Mine was built at the Pontiac Assembly Center at least that is what the door sticker sais I'm sure it's US built. I wonder how many different plants there is I know my dads was built in Canada.

Mine looks like the first one!! I have an 05 with manual controlls..
http://dieselplace.com/forum/attachment.php?attachmentid=7963&stc=1&thumb=1&d=1125066382


I need a few people with 04s and 05s with both manual and auto A/C to do me a favor. Can you lower the black cover below the glovebox and check what the HVAC area looks like? I'm betting GM didn't change the HVAC ducting, but I have to make sure first.


Tell me if the area looks like one of the two pics below.

http://dieselplace.com/forum/attachment.php?attachmentid=7963&stc=1&thumb=1&d=1125066382 This is the filter area for those with Auto A/C. Notice the little "nub" for the screw is right even with the filter boss?

http://dieselplace.com/forum/attachment.php?attachmentid=7964&stc=1&thumb=1&d=1125066382 This is the filter area for those with Manual A/C. The little "nub" for the screw will be just above the "scribed" area and even with the lower metal dash brace under the glovebox.

L

Hey Bac since mine is the manual unit and it looks like the first one that is an auto I bet the diference is between truck plants and not if it's a manual or auto ac unit. Mine was built at the Pontiac Assembly Center at least that is what the door sticker sais I'm sure it's US built. I wonder how many different plants there is I know my dads was built in Canada.


I do think you may be right. I should have done some checking first. Now I can't edit that post.

I checked about 10 trucks on the route today, and all of them had picture #1. Maybe Jeff had a "bastard" HVAC unit??? Oh well, at least the majority have the "easier" cover to make!

I thought all the trucks were built in Flint/Pontiac?

I also came up with an idea for someone who DOES have picture #2. I won't have them cut up the side at all. That way the cover only has to seal in one plane instead of two. That was the b*tch of Jeff's cover..to get those two planes right.

As soon as I get Nick some $$, then I can get the directions and templates made, buy the filters, and get the kits made up for shipping.

TheBac, I've got the 05 w/ Auto A/c check out my pix in Post #53 on page 6 of this thread.

OK, so it looks like Pic #1 is the clear majority.

This is what I'm planning on including in the "kits", when I start getting them going.

1) cover
2) cover screw
3) cutting template (made out of a removable sticker...it will have reference points of the screw hole and the sides of the HVAC unit, with an outlined 1 1/16" x 6" for cutting)
4) cardboard piece for inserting the filters
5) filters (2)
6) sticker to place inside your glovebox stating "this vehicle retrofitted with cabin air filters, use ACDelco CF104 or equivalent", with date and mileage when filters were added
7) Instructions

Think I should include anything else? Opinions?

Would you guys prefer the standard ACDelco filters or the NAPA charcoal ones? Obviously the price would be higher if the charcoal filters are used.

Tom,

I do believe you've got it covered.

What kind of difference in pricing between the two types of filters?

Steve

I'm thinking they're about twice as much as the regular ones. I'll have to go check out those Fram ones that IdleChatter was talking about, or the Bosch ones that Tony was posting about.

Awsome!!! I'll probally buy 2 from you one for me and one for my dad! NAPA charcoal would work fine for me but either or I guess you can always change if you want1!!!



YOU ARE THE MAN!!!:grd: :grd:

Ok, just an update.

I thought maybe I could possibly find an OEM GM filter cover. I thought the Escalades may have still had the filters OEM. After perusing the GM parts computer at my dealer (the nice lady was there!) I found that no GM model truck had the filter setup we need. So I definitely have to make the covers.

I guess I'll have to get a few sets of both style filters, and then make prices up depending on what style a person wants.

Tomorrow, my wife is going to set up the Print Artist program so I can make the templates (she's an absolute whiz on that program). I'll also have her set up the glovebox stickers too.

The first batch of aluminum is cut. I just have to clean them up, drill holes, and paint them.

Monday, I'll try to get a check off to Nick via UPS so I can get the Limited Vendor status going. After I get the ok, I'll put up a post in the vendor section about the kits.

I will try to be ready ASAP. You know how it goes, there's always something unforseen....

Awsome! I want the first kit!! LOL I asked for it first damn it! :muahaha: :muahaha:


Ok, just an update.

I thought maybe I could possibly find an OEM GM filter cover. I thought the Escalades may have still had the filters OEM. After perusing the GM parts computer at my dealer (the nice lady was there!) I found that no GM model truck had the filter setup we need. So I definitely have to make the covers.

I guess I'll have to get a few sets of both style filters, and then make prices up depending on what style a person wants.

Tomorrow, my wife is going to set up the Print Artist program so I can make the templates (she's an absolute whiz on that program). I'll also have her set up the glovebox stickers too.

The first batch of aluminum is cut. I just have to clean them up, drill holes, and paint them.

Monday, I'll try to get a check off to Nick via UPS so I can get the Limited Vendor status going. After I get the ok, I'll put up a post in the vendor section about the kits.

I will try to be ready ASAP. You know how it goes, there's always something unforseen....

Tom, that is a great idea and a good way to help and make a few bucks too!

:ro) :eek: :eek: :eek: :eek: :eek: :ro) I can't wait, My g/f and her friends that go mudding with us are gonna love it.!!!

I figure anyone that deals with a lot of dust may like this......don't really know how it helps when you're out muddin.....

BTW, sent the check to Nick today.

Thanks for the compliment, Mitch....you're one of the people that gave me the idea.

Well where we go mudding there is alot of dust and sand, my g/f has bad allg.


I figure anyone that deals with a lot of dust may like this......don't really know how it helps when you're out muddin.....

BTW, sent the check to Nick today.

Thanks for the compliment, Mitch....you're one of the people that gave me the idea.

Well where we go mudding there is alot of dust and sand, my g/f has bad allg.

Gay friend bad allignment?:joke:

Can any 2006 owners chime in as to what their HVAC unit looks like? I'm curious to see if they are the same.

Now that we got the wheels turning, your covering the whole scope now. LOL ;)


Can any 2006 owners chime in as to what their HVAC unit looks like? I'm curious to see if they are the same.

<--------------Lookie here!!!!! I'M LEGAL! Thanks Nick!!!!! :thumb:

I hope to have the first batch of covers done soon. I'm waiting on the metal shop to finish cutting some more aluminum up, then they're off to the powder coater (I tried painting one yesterday, and it looked like chit.)
I found I can't make a decent template, so I'm going to try to have a drawing with measurements in the instructions. It's actually very straightforward once you get under there to start cutting.
Just have to snap a few more pics, too. I'm gettin there.....

AWSOME!!!:ro) :ro) :ro)

<--------------Lookie here!!!!! Thanks Nick!!!!! :thumb:

I hope to have the first batch of covers done soon. I'm waiting on the metal shop to finish cutting some more aluminum up, then they're off to the powder coater (I tried painting one yesterday, and it looked like chit.)
I found I can't make a decent template, so I'm going to try to have a drawing with measurements in the instructions. It's actually very straightforward once you get under there to start cutting.
Just have to snap a few more pics, too. I'm gettin there.....

Hey Tom,

I'd like to put one in the wifes '04 tahoe... You may be able to expand who you can sell to and quit the day job...I'll crawl under there soon to let you know if I can use one...

or...

if anyone had an '01 '02 tahoe...did yours have the filters?

Hey Tom,

I'd like to put one in the wifes '04 tahoe... You may be able to expand who you can sell to and quit the day job...I'll crawl under there soon to let you know if I can use one...

or...

if anyone had an '01 '02 tahoe...did yours have the filters?

Yes we had an '02 yukon and it had it....

Congrats Mr Bacon! NOW............:grd:


<--------------Lookie here!!!!! I'M LEGAL! Thanks Nick!!!!! :thumb:

I hope to have the first batch of covers done soon. I'm waiting on the metal shop to finish cutting some more aluminum up, then they're off to the powder coater (I tried painting one yesterday, and it looked like chit.)
I found I can't make a decent template, so I'm going to try to have a drawing with measurements in the instructions. It's actually very straightforward once you get under there to start cutting.
Just have to snap a few more pics, too. I'm gettin there.....

<--------------Lookie here!!!!! I'M LEGAL! Thanks Nick!!!!! :thumb:

I hope to have the first batch of covers done soon. I'm waiting on the metal shop to finish cutting some more aluminum up, then they're off to the powder coater (I tried painting one yesterday, and it looked like chit.)
I found I can't make a decent template, so I'm going to try to have a drawing with measurements in the instructions. It's actually very straightforward once you get under there to start cutting.
Just have to snap a few more pics, too. I'm gettin there.....
CONGRATULATIONS Tom!!! You're now on your way to financial freedom. :D :ro)

Hey Tom,

I'd like to put one in the wifes '04 tahoe... You may be able to expand who you can sell to and quit the day job...I'll crawl under there soon to let you know if I can use one...

or...

if anyone had an '01 '02 tahoe...did yours have the filters?

I will be starting a new thread soon with details, ordering info and pics.

This mod should work on MOST all the 03-up trucks, wether they be Tahoes, Suburbans, Yukons, Avs, Silverados or Sierras. I think, but am not completely sure, that the Escalades still have filters in the 03-ups, but in a different shape and location. (that won't work for the other trucks for some reason). I have to do some more checking on that one.

Yes, it could get veryyyyyyy interesting......thats a lot of potential customers. Who knows marketing around here? :lol:

CONGRATULATIONS Tom!!! You're now on your way to financial freedom. :D :ro)

Now thats just plain funny. Thanks (I think) :lol:

Congrats Mr Bacon! NOW............:grd:


Mark....you actually posted!!!!! Now I can officially say, "Welcome to the Place!!!!" :D

Ya I posted, even though I drive a gasser camaro. :eek:
I know how hard you are working on this cabin filter gig. Becoming a limited vendor is a great idea for you.
:phatyo:

<--------------Lookie here!!!!! I'M LEGAL! Thanks Nick!!!!! :thumb:

Congrats, my friend!!! You deserve it after all the hard work and hours spent on this!!!

Yo Tom,

Shall we now start to call your B.B.T the Mach I? Theres goes, goes Speed Racer, he's a demon on wheels!

http://www.thedieselgarage.com/forums/images/smilies/umno.gif
I don't think so, Mark.....

Any update? Great job on limited vendor status! :ro) :ro) :ro)

http://www.thedieselgarage.com/forums/images/smilies/umno.gif
I don't think so, Mark.....

Waiting on my metal guy...:mad:

Also working on the wording for the Sale thread.

Well get on it Tom.......Just kidding;)

Let us know....I'm up for 1 of the TB Air Filter Kits.

See this thread:

Cabin Air Filter Retrofit Kits (http://dieselplace.com/forum/showthread.php?t=48973)

Tom,

Would please post a pic of the dremel tool/attachment that you used to cut yours & Tom's HVAC?

Steve...it's hard to see in the picture, but it is a 2" cutting wheel. We were able to do the whole cut with that on Tom's HVAC unit. But on mine, with the funky HVAC housing, I had to use a cutting bit to do the horizontal cuts because the blower motor stuck out more than Tom's.

Tom and I were using my dremel and it is the straight version. If you can find a 90* dremel with the 2" cutting wheel you'll have a much easier time of cutting the slot. The blower motor gets in the way of cutting as you can see in the photo.

I hope that this helps.

Jeff

Tom,

Would please post a pic of the dremel tool/attachment that you used to cut yours & Tom's HVAC?

Thanks Jeff !!

I just bought a Dremel kit ( ):h ) and has the flexi shaft attchment that should work out nicely.
Waiting for Tom to receive my order and ship it out to me! :ro)

I have not seen the install instructions yet, so here is an uninformed question - Any idea how much air flow is restricted/reduced by the introduction of these filters?

I assume the filters runs across the air flow?

On my wife's Maxima, I have ran without the filter and the air moved much more powerfully out the vents with the filter out. The Nissan was designed for the filter. Wonder what will happen to the Chevy Truck air flow with filter installed.

Any back pressure issues to be concerned with?

I hope you understand when I say I won't send out the instructions with out a kit being bought.

Anytime you install something in the flow path, whether its air or liquid, you'll get some restriction. Jeff and I did not notice any major impact on our systems. In fact, Jeff thought his A/C was COLDER with the filters installed. The filters install right in front of the evaporator.

You obviously cant forget to check your filters on a couple times a year schedule, and replace them every year. As the filters get filled with gunk, the airflow will decrease. We figure that may be one of the reasons GM discontinued them...because people didn't check them, they complained about reduced A/C performance, and GM had to do warranty repairs for a serviceable item.

Hope that answers your questions....