[Browneye]

Update for January 2025 - I still get the occasional request to build one of these - people buy a used Colorado and then go looking for accessories. My original, the prototype, is still installed, still going strong - works just great.
I have to raise the price to $270 for shipping costs (they are more on ebay). Material costs are up just a bit, but I don't have a commercial discount UPS rate anymore and it runs about $50 for domestic shipping - which is ridiculous since it weighs about 15lbs.
Lead time is still just a couple of days - mostly I keep build materials on hand. Shipped about a dozen of them last year.

Update for October 2023 - I have relocated to Yakima WA - can still build and ship in a couple of days. Costs and shipping is up - price is now $250 shipped.
Just post or PM if you have any questions or requests. Yes, LOTS of them sold over the years. And I'm still using my original prototype one!

Update June 2021 - Yes, still making these for X-cab owners around the country. The new ZR-2 has been popular with the extended cab - evidently it's the only way you can get a x-cab with a diesel. In any case, this platform has become even more popular - the inside configuration and dimensions remains the same going back to 2015.

For taller drivers we notch the top back behind the seat, and for the passenger side as well if desired. There are pics of this along about page 5-6 or so. If you're interested in getting one just let me know your height and pants length and I'll size the top accordingly.

Cost for a finished platform is $200, plus pack and ship UPS Ground to continental US for $35 - Total $235

Thanks for all the interest! PM for more details or to place an order.

**
Now to the original story from early 2015....

Well, we had a lengthy discussion, the wife and I on cab configuration when we were shopping. The crew-cab 4-door is a really nice layout, but for me the bed was way too short for hauling motorbikes and there was no way I was buying the long wheelbase truck as a 4x4. So it kind of got down to the point where it was a go or no-go on even getting a truck as it had to be the extended cab. She looked at the back seats and said no way is this going to work, I can't even fit in there. I told her to think of it as a 2-seater with space for the dogs. We've had pickup trucks going back more than 40 years and a truck seat used to seat 3 in a pinch and that was all there ever was. We just won't have any passengers, or maybe just one in a pinch. The extended cab is really too small for an adult anyway. They'll have to bring their own car, or we'll take two.

So once we settled that, then there was the dogs - our 3 Pomeranians (no we didn't CHOOSE to have 3 dogs - we inherited the third LOL), they are 8-12lbs so there's plenty of space for them and one usually rides on a lap. But that back seat configuration doesn't work for dogs. There's the cup holders and the cubby for seat belts to sit in. And the seat bases are really short with a big gap behind the front seats. Even hauling groceries and such is a PITA with the way it is as built.

I got to looking at it and thought the seat cushions are easily removed - there is a bolt on each side that also holds the seatbelts. And the backs are similarly easily removed. But now we have those two stupid little plastic storage bins and the cubby and drink holder in the middle. My thought was to build a platform in place of the seat bases. But then there would be no way to ever use the seats even if you really wanted to. I wanted to keep that option if possible should the need arise.

Next idea was to build a plywood platform that sits above the seat pads and leave everything the factory put in there intact. This also preserves the two storage bins, granted they're small, but at least you can throw some emergency things and stuff like that in them.

I got a basic design going in my head and some measurements and walked thru my local Lowe's home center store for some supplies. Here is my parts list:

Half sheet of 1/2" birch-faced cabinet plywood - $25 (EDIT 6-25-2021 - I just had to pay $80 for maple-faced plywood, everything is sold out and what's left has doubled in price)
3M spray adhesive for carpet - $9
A 4' Piano hinge - $10
Pack of #8x1/14" wood screws - $1.25
One 8' stick of 1x2 milled pine wood strip - $5

I had a bottle of wood glue, and I have all kinds of woodworking tools. I have built cabinets and boats and houses and such. Definitely makes it easy when you have what you need on hand.

Lowe's didn't have any carpeting that looked automotive, and no black, so I went down the street to Pep Boys auto parts and got a 3x6' piece of black auto carpet. $15

First step was to cut the top to size. Fortunately the width from side to side is perfect at 4'. Front to back is 18" from the center console to the jack cover. Easy. Next was to get a feel for height and level - I matched the levelness to the box so when the truck is level the platform will be level.

Birch-faced cabinet plywood is really nice to work with. It mills easy and is perfectly flat and square. Cost is about 20% more than plain fir CDX but so much nicer to build with. CDX or even AC panels are common plywood, like you put on the sides or roof of your house or floor. But it always has some twist 'till you nail it down. Plus it picks up moisture quickly and warps, not what I wanted to deal with for this project. I didn't want OSB or particle board either - and wanted to keep it lightweight.
Weight is about 34lbs for a full sheet, so there's about 12lbs of material here, plus the 1x2 pine strip. Very easy to handle for installing and removing the finished platform.

It turns out that the seatbelt retractors make a perfect support for the back at the height of a 1x2.






Next I break out my cabinet tools, countersink bits and glue and screw the back support to the platform top. I set it back from the edge about an inch so it rides square on the seatbelt caps without digging into them. Carpet will add a lot of cushion to everywhere the assembly touches the truck.




Took a bevel from the floor to the driveline hump, centered it, and cut out the front of the platform support. I used a 3/4" radius to the lower edges, the hump cut out, and the front of the platform top. Then rounded over all the exposed edges with a wood plane.









Next I can trial fit everything and figure out where the piano hinge is going to go. By setting it back against the bins and with the floor hump cut out, the whole thing locks into place. It cannot move forward or back, or left or right, it fits perfectly into the space.






I'm going to break this into a couple of posts so it doesn't get so long...

 

[Browneye]

Since the piano hinge comes in a 4' length no cutting required, just a few dozen little screws. A power driver is the way to go here. I like to drill a tapered pilot hole, the screws start and drive easier and no wood splitting. Just don't drive them too hard or they strip. Piano hinge comes in brass or chrome finish - same price.



With everything assembled I can now check all my clearances. It clears the rear seat pads on top by about a quarter inch. There's quite a bit of cushion on the backs of the front seats so they will slide pretty much all they way back in the tracks. I'm 5-10" with 31" inseam and with my seat adjusted for normal driving there's about an inch between the platform and the back of the seat, more if you squish the back of the seat - there's quite a bit of give to the back of the seat. And there's room to move further back for a taller driver, or to recline about halfway. In a pinch I would move the seat base up a couple of cogs and then I can get the seat to recline about 60%.








Tested it out with a couple of common cargo pieces as well. At 18" wide it's perfect for grocery bags, boxes, a cooler. I even had a plastic storage bin hanging around that fits perfectly in there.

Since the rear cross support sits on the seat retractor housings I figure 40lbs max is a good bet. Too much weight and it would crush those plastic housings. I popped one off and there is good webbing internally that sits on the metal part of the seatbelt mechanism, they are plenty strong. Nice design here from GM.

Again though, I would limit weight on this setup. For us, it's grocery bags, some gear, or the little dogs. Would hold any dog that would fit inside this compartment - after all it is just 6 square feet - 18" by 48".






And finally, if we need to use the seats it folds flat and can be tossed into the box or left in the garage.
Sand it all smooth and prep for carpet covering.



Smooth top ready for covering. I rounded over the edges well so it wouldn't cut into the front seat backs even if they get mashed down against them.




Finishing it up on the next post...

 

[Browneye]

Covering it with automotive carpet is the last step. 3M Super 77 adhesive is really easy to work with and sticks like crazy. You do have some working time, but it sticks like contact cement.

Left a margin all the way around so I could wrap it around the platform edges and rear support, put a 1/4" staple every few inches. It could also be upholstered in the say way. For me the carpeted top is perfect. Makes for a flat-floor of carpet like a SUV.



With the surfaces carpeted over it's ready to install and test out with the doggies. My next project will be to make a fabric dog bed with a raised edge roll all the way around. That will cover all the little openings at the edges and hold the dog hair. When the dogs get out the bed can be removed along with all their hair. What a PITA! :lol:





Wifey thinks it's all good.



The whole thing is easy to flip up to gain access to the storage bins below.
One side, or both. Just flip the seat forward so there's room to raise it up.

The half inch plywood is plenty light and plenty strong - no bowing at all with weight on it. It's very solid.






There's still room to get to the USB ports for charging, and cigar lighter plug, in the back of the center console.




And there's room for cargo under the front seats in front of the platform base. Yes, you would have to remove your cargo and raise it up to get to the jack and tools.



Still plenty of room to recline or to move the driver seat back. If you're over 6-2 or 3 I would make sure the seat can slide all the way to the rear of the track. I think I have a cog or two more to go. As I mentioned, in my normal position there's about an extra two inches of room behind the seat. Plenty of room for the passenger seat too, even for reclining.






Thanks for reading along...hope you enjoyed this little project. Build time was about 3-4 hours. I'll bet I could make one again in about half the time. There was a lot of measuring and trial fitting and figuring out how everything would work.

I can tell you we will get a LOT of use out of it. The space is much more usable. Now I am totally in love with extended cab Colorado!
Maybe it would work for you too.

::chevy::

 

[goldwing1800]

That looks tailor made, great job, better than a planter box

 

[Stevef]

Nicely done-looks like the dogs approve, too! I like the way you set it up to hinge up out of the way to get at the underseat storage, too. If you could whip those out in a couple of hours with a pattern you could probably sell a few...

 

[RatRacer]

Great how to build, and execution. A nice, simple, portable design to increase the functionality of the space.
Good job, and thanks for sharing.

 

[ocnblu]

Nicely done! Looks like you've thought of everything, it looks great. I wonder if the jumpseat headrests are removable. Won't be hauling ppl back there, the headrests seem like they'd hurt visibility.

 

[rkj__]

Excellent write up. Nice design. Well built.

This does make the space way more useful.

What is the height from the top of the platform, to the bottom of the rear window?

Sent from AutoGuide.com Free App

 

[RatRacer]

Nicely done! Looks like you've thought of everything, it looks great. I wonder if the jumpseat headrests are removable. Won't be hauling ppl back there, the headrests seem like they'd hurt visibility.

They do remove, and stow in holes in front of the seat base, just like the seat back. Adjusted all the way down, they don't obscure visibility out the back for me @ 5' 10".

 

[The Kingdom]

Great step-by-step instructions and pictures!


EDIT: You might consider these:

 

[MAJFRIZZ]

Chris,

Looks good Chris.

Bob

 

[Browneye]

Thanks for the kind words. I love doing this stuff. My first foray was a 1964 Ford Econoline van back about 1975. Some of you aren't old enough to remember all the custom vans from the 70's. I was the youngest member of the local van club and won trophies showing it - once even at the Seattle Coliseum for some kind of custom car show. I've been doing custom paint work for over 40 years as well. 8)

I wonder if the jumpseat headrests are removable. Won't be hauling ppl back there, the headrests seem like they'd hurt visibility.

Already removed them! I thought the same thing...they're gone. I may try to come up with some kind of plug or cover for the two post bases.

BTW, those silly cable thingies can be tucked into the top of the seat-back to tidy up. I may even look at removing them although they could be used for a cargo net or something I suppose.

Only the passenger side headrest fits into the seat base - it's for placing a toddler carseat. The driver side doesn't have the holes. You can see that in my flipped-up bin access.

What is the height from the top of the platform, to the bottom of the rear window?

20"
Too bad the rear side windows don't at least prop open. I'm a candidate for a sliding rear window...we'll see. If they're not to expensive it might be a nice additional feature, especially for the dogs.

Nicely done-looks like the dogs approve, too! I like the way you set it up to hinge up out of the way to get at the underseat storage, too. If you could whip those out in a couple of hours with a pattern you could probably sell a few...

Likely yes. While I enjoy build projects for myself my time is worth more than what money the effort might produce selling them. I dunno, this one might really take off for the number of this style truck that is sold. Could do one for the Tacoma too. And really, I don't know of anyone that regularly puts passengers in an ex-cab.

Ideally they would be stamped out of fiberboard and made as cheaply as possible (in china LOL). But that would ruin the effectiveness.

I wonder if there would be buyers for $150. No wonder campers and RV's are so expensive, and they get it down to cookie-cutter level production. <shrug>

Great step-by-step instructions and pictures!

EDIT: You might consider these:

Oh, the cargo net thingy for the space between the seats. Great idea for bigger dogs in a back seat. I suppose if you wanted to block that area off that looks like it would work well. For us, we want the dogs to be able to pass through.

I also like to have the seats be able to move independantly and this would prevent that. I had considered hanging a nylon strap from the headrests to support the front of the platform. Then thought twice for just this reason. Would also make putting in and taking out a hassle. What I have just lifts in or out very easily. The seats more or less trap it in there, so you do have to move the seat backs up a little to get clearance.

 

[CaryBosse]

Looks nice, but if you were going to mass produce, thermoformed plastic would be the way to go - would allow for some 3 dimensional features at that point.

 

[Rememo]

Very nice! You kept it simple, yet functional. I love that it folds up for under-seat storage access. Nice job.

 

[k7tnt]

Very nice! You kept it simple, yet functional. I love that it folds up for under-seat storage access. Nice job.

+1 very nice, good job!

 

[BobZ06]

Love to see good old ingenuity at work! Great Job!

 

[Searun]

Ditto on the great job.
A very practical application.

 

[battousai2000]

Chris, when I buy I am probably going to go with the extended cab and I would love to do this. Would you be opposed to making a paper or cardboard template of your setup and sending them to me to save me some time and trial and error? I of course wouldn't mind providing some compensation

 

[Browneye]

Let me see about making some basic drawings and dimensions.

It turned out really simple and so far I can't think of anything I would do differently.

I supposed it could be taller with more storage under, and a higher platform, but it would need to be cut back for the front seat backs, and you would lose access to the USB ports and cigar lighter.

 

[george88gta]

Great job! Nice to see that there are folks out there that consider their dogs as family members. I inherited two Boston's. They loved my S-10 crew cab and they are happy with the Colorado crew cab. The bigger of the two likes to stand on the back seat with his front paws on the console cover. Cold days he has his nose pointed to the dash vents for heat and in the warm days, facing in to the cold. No sticking his head out the window! I have blankets to protect the upholstery, but they pretty much have free reign.