We slept in the 4Runner for the first time last weekend on the beach.
We used a Luno air mattress specifically for the 4Runner. It was great, and very comfortable, until my side deflated. Luckily we only stayed one night in the 4Runner, and Luno is sending me a new mattress, but still sucked. I will say with the Luno fully aired up, but cant really even feel the unlevel transition in the back of the 4Runner.
I'm 6'3", and have a molle panel on my liftgate, so I was crammed a little, but still doable if you bend your knees. My wife and son are small so that was possible.
We used an Icy Breeze cooler in he front seat for air conditioning, but it got too hot so we actually ran the 4Runner most of the night. With it being a 2020, and with the beach breeze, we didnt worry about fumes.
I don't really have any good pics of the set up except for this one of my hot wife and my son the morning after once we folded up one of the seats.
We also had suction cup fans on the windows, but I need to create a constant power 12v for when the truck is off.

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2020 Army Green TRD Pro 4Runner | IG: @TRDHULK
35" KM3s | Kings | RRW RR6-H -25 Wheels | Cali Raised LED Sliders | + lots more
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