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MidGate Sub Box Questions

Bruizza

Full Member
Joined
Apr 22, 2009
Messages
480
For those of you that have replaced your midgate with a sub box how much room did you lose in the bed.  I realize that this amount is going to vary based on the size and number of subs.  I just want to get a rough idea of how much room I might be losing. 

Also how easy is it to swap the box and the midgate back and forth?  I know I would need to do this a few times a year like when we do our big boating trips and snowboarding trips.  I don't mind swapping them if it is like a half hour thing.  I will definitely mind if it is a 3 hour ordeal.  Found a midgate box for sale locally for what I consider a good price.  Trying to get my ducks in a row before I drop the $ though.
 
I'm on my 3rd Midgate box.First one was a fairly simple build.  I took the midgate out, traced it on a sheet of 3/4" MDF, then made a ring 2 1/2" wide around the perimeter of the first cut out (to get the width of the gate closer to the factory width). I then had to add two blocks about 5" wide at the top (making it 3 layers) to properly mount and position the factory hardware.  I then used a factory 3 cubic foot box for two twelves and through bolted it to the midgate from the interior side and sealed it up. It was still able to fold down, and removing it was as simple as taking the 8 lag bolts out and disconnecting the speaker wire, about 15 minutes.  I only ever had to remove it one time though, I mounted it up off the floor of the bed about 5" so that I could slide my snowboards under it.
Second one was a slightly modified stealth box housing two Kicker L5 12s. same situation, even though it was closer to the bottom of the bed, I was still able to slide my boards underneath.  The one that is in there now houses 2 JL 13W7s and is significantly larger, no folding or room underneath.
I built this one the same as the first one, it just has a much larger ported enclosure behind it.
I am still in Tennessee and won't be home until next Monday. not sure how many photos I have of each of them, but I'll post some up what I have when I get home.
Not sure what you are looking to spend, but AK Audio in Rome, GA will build a midgate box built to any specs you want and ship it anywhere in the continental U.S. for $500.
They have pre-built ones that meet the specs of most subs for for $400.  I basically stole their design for my first one.
Post #157 in this thread is my first one
http://chevyavalanchefanclub.com/cafcna/index.php/topic,73523.150.html
 
I went ahead and bought this one. It's AK Audio and has 4 10" kicker comp r subs in it. Was only $350. Same box on eBay was $439 plus shipping so $539. The subs retail for $130. Figured that out it over a grand retail. It is used but appears to be in good shape in the pictures. I'll snag it from the guy one of the next 2 weekends. We live about 300 miles apart.
 
If you go to ebay and search avalanche sub box you will get quite a few results.  As far as I know the midgate has never changed so the boxes are good for 02-13s.  AK Audio is who built mine and they have a huge selection.  They will also custom make you one to the specs of your specific subwoofers.
 
:cool: I went with the newer slim JL Audio Stealthbox that comes with 2 12TW3's and the space lost is pretty minimal.
Would definitely recommend. You don't have to take out the mid-gate with this setup, the back of the box is the same as the cladding, you would need to store the glass elsewhere though, front seat or garage etc.  (y)
 
If anyone happens to know after 2 years. What is the best way to seal the sub box? I get a little water coming into the truck in hard rain. I added hard Tonneau covers to try to help but water still comes in. I don't want to start taking silicone to the truck because if I want to sell the box, I still have the original to replace it with. Any advice would be greatly appreciated.
 
Something is wrong with the install or setup
I see in your signature that you have a JL Audio Midgate box.
I have had mine in the 02 for over 12 years without it ever leaking into the truck.
Sounds like a different issue maybe the drains near midgate are clogged etc.
good luck and welcome
 
AzianRedneck08 said:
If anyone happens to know after 2 years. What is the best way to seal the sub box? I get a little water coming into the truck in hard rain. I added hard Tonneau covers to try to help but water still comes in. I don't want to start taking silicone to the truck because if I want to sell the box, I still have the original to replace it with. Any advice would be greatly appreciated.
Maybe water is coming in from somewhere else?

DO you know exactly where water comes in at?

Check Problems Water LEAK section for threads where people had waterleaks
 
AzianRedneck08 said:
If anyone happens to know after 2 years. What is the best way to seal the sub box? I get a little water coming into the truck in hard rain.

What do you mean by "into the truck"? into the cabin behind the seats? into the bed and onto your box? Do you have any photos?
 
If you are getting a small amount of water into the truck is your rear window trim cracked? Water will leak around that into your truck.
 
I honestly didn't look anywhere around the midgate. It didn't rain a lot when I got the truck, so I didn't pay much attention. I ran it through a car was a few times and everything was fine, at least to the best of my knowledge. I know that when I put the sub box in that's when I started to notice problems. Water collects at the bottom of the under the box, where the stock midgate sits. The hinge that flattens when the midgate is down is pushed back a bit now. I'll get pictures tonight, and get them up in a few hours. In that time I'll also check other seals and things around the back.

Thanks for the advice and help yall. I really appreciate it.
 
I made a 3x12" alpine speaker box and integrated it with my Midgate by cutting a box shape out of the midgate back and leaving the front in tact with holes for the speakers cut out. The plastic is significantly strong and will hold the box in place. I used significant bolts to hold the box in place and also sealed where the two come together with flexible sealant and coated the box with flexible bedliner. It is not leaking at all. I think my drip rails are leaking now but since I will be pulling the sides back apart to integrate my amplifiers I am not dealing with it right now.
 
Working on mine as we speak ...
gallery_5_7_43114.jpg

Hopefully the end result will be a positive !!!
 
Calicak89 said:
doesn't look like you have broken the midgate flap yet, so I'd say you're off to a strong start.
I took it out so I can make the baffle to fit the rubber surround. At the time of this pic, I was picking up my enclosure from the builder and wanted to test fit.
So far, nothing has "tore up" taking things out ... I plan on starting a build pic log here soon. Thanks for posting !!!
 
Its all going to depend on your application. For example, I had to build a big ass box for my subs lol.
https://youtu.be/0Oj5kClH0po
 

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White Lightning said:
How did you seal up your enclosure ?? From water leaking into the bed that is ???
Rattle can or roll on bedliner and Rustoleum Restore deck paint are usually the products of choice
 
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