The fire crackled under a starlit sky, casting flickering shadows on the circle of camp chairs and half-built rigs nearby. The air smelled like pine. Just how these guys liked it.
A Simple Question Sparks a Big Idea
Jim took out his thermos, looking into the flames.
“You ever think about making a pass-through in a box truck? Like Joe’s ambulance setup?”
“Wouldn’t that be convenient to hop into the back without jumping out in the rain?”
The group nodded in agreement.
Early Solutions: Neoprene and Soft Tops
“Wouldn’t be easy,” said Randy, leaning back in his chair. “I recall this guy who tried it. He used neoprene from an old wetsuit to seal the opening between the cab and cargo box. Not perfect, but it worked.”
Jim thought about that. “Neoprene, huh? Seems like a reasonable solution—it’s water-repellent. But it might take a lot of cutting and fitting to really make it watertight.”
Then Jack, sitting in his tall chair with grease-stained hands, chimed in. “Maybe try some convertible top material. Of course, you’d need some sewing machine skills. But sealing it properly? That’s the hard part.”
Randy nodded. “You also need to make sure you’ve got a solid surface to mount the seal. No point trying this on a flimsy wall.”
Tom’s Big Build: A Bread Truck Conversion
From across the fire, Tom stirred his coffee and spoke up.
“Well, here’s what I’m doing. I’m putting a 23-foot aluminum bread truck body on a deuce frame.”
Everyone turned to look.
“Yep. Plan is to walk right through from the cab into the living quarters. No more climbing in and out.”
Jim grinned. “That’s pretty cool. What are you going to use for the pass-through?”
“I’m still exploring options,” Tom said. “Thought about installing an access door. Maybe a removable seat base and a zippered soft top.”
Jack leaned forward. “You need to let us know what you decide. I’ve got an old bread truck body too. Planning to turn it into a Jeep hauler. 5.9 Cummins. Fold-down bed, running water—the works.”
Tom nodded. “Been working on it every weekend. My wife says I’m obsessed. I told her, maybe I’ll build her one next.”
Everyone chuckled.
The Real-World Solution: Accordion Rubber Boot
Across the circle, Phil, the quiet guy who’d been poking the fire with a stick, finally chimed in. “When I do the pass-through on my truck, I’m using an accordion rubber boot.”
The fire popped. Randy raised an eyebrow. “Accordion boot? Like the semi trucks and truck toppers use?”
“That’s right,” Phil nodded. “It’s flexible enough to allow movement, seals tight, and you don’t need to be a rocket scientist to make it work. Just line up the openings, slide it on, and you’re done.”
Tom leaned forward, now fully interested. “You know… I’ve seen that kind of setup on a Peterbilt sleeper. To finish off the interior, they added a vinyl cover that snaps over the boot.”
Jack grinned. “That’s what I’m talking about. Built for real-world use. Wind, rain, flexing chassis… it just works.”
The Final Verdict: Best Tool for the Job
Jim nodded slowly. “Still, that’s the kind of solution I was searching for. All these ideas—cutting into the cab, neoprene seals, hatches—those are options. But that accordion boot? I believe it’s by far the best solution for a pass-through.”
Tom leaned back and looked up at the stars. “You know what? That just might be the answer I’ve been hunting for. Time to ditch the zipper idea.”
As the fire burned low and the whiskey made its way around the circle, the group had quietly settled it:
The best, most battle-tested way to build a pass-through between a truck cab and a camper or cargo body wasn’t a hack. It was the accordion rubber boot—designed for the job, built to last.
Campfire Wisdom Recap
If you’re building a rig and want pass-through access from your truck cab to your camper, bread truck body, or service box:
- Frame both cab and camper sides with hard walls
- Cut a clean opening between them
- Use a rubber accordion boot for a flexible, weather-tight seal
Rubber Boot Seal
You can order rubber boot material for your special project requiring pass through access. These seals are extruded from a durable EPDM synthetic rubber and incorporate a flexible spring steel clip for attachment to any flange. This material is sold by the foot. Choose between accordion boot or compression boot.