I got the idea from some of the threads on here and YotaTech. I wanted something easy, quick and relatively cheap.

I based mine off of this link:
Sleeping deck for 4Runner

I basically followed this except that I didn't cut my piece into (2) 4'x3' pieces...I cut it is a 6'x4' as I thought it might be more stable. The rear seats will have to come out (not the seat backs, just fold those down) but taking out the seat bottoms takes all of about 2 minutes. (2 bolts on each seat).

I used 6 - 10" threaded pipes, 2 - 18" threaded pipes, and 16 flanges. All of the pipes were 3/4" and the flanges were also 3/4". I used 3/4" plywood for extra strength. I drilled small pilot holes for the screws (wood screws, 3/4") and then screwed it all together putting on the 18" pipes on last.

I used a futon mattress for the top. It is a little high (close to the ceiling) but it should be fine...after all, I won't be living in this (yet).

Result: Tons of space underneath. I didn't put any pipes in the middle (going lengthwise) so that I could shove a dog crate etc under there (folded up of course!). With 3/4" plywood I don't think you will need any extra support in the middle....I got on there and jumped around and it feels very solid. I am hoping to support myself and 2 dogs.

Took me about 45 minutes or less to get it all done.

Tools used: circular saw to cut plywood, cordless drill for pilot holes and screwing the screws/flanges

Total cost: $154 (included ALL parts, plywood, screws)

Looks good. Lots of room underneath!

Looks good man. I have a futon mattress laying around and been thinking about doing something like this.

Drove to Iowa last week from Alabama...had the platform in there with the futon mattress on top. We didn't even have to take our Yakima cargo top b/c we could fit everything under the platform! Took our 2 dogs and they instantly loved it...they could lay down at the front and hang their heads in between the driver and passenger seat while driving. My wife and I took turns driving. I am 5'11" and could sprawl all the way out...with 2 dogs in the back and it was comfortable. Takes less than a minute to put it in the back of the 4runner and about that to get it back out!!!

The 3/4" plywood is the way to go...doesn't even start to bend when you are on top...I have the legs running close to the side so we could slide a dog crate and everything in the middle.....works great!

Keep in mind that if you don't put a futon mattress you might need to put carpet on the platform so you don't slide around...but the futon mattress fits PERFECT...and doesn't slide at all.

Very nice platform. We used our platform to sleep the weekend in sturgis. It was windy and rained one night and we didn't even hear it. Sure beats a tent!!!

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