Howdy folks! Imagine you're all cozy in your sleeping bag, drifting off — and you awaken to a stranger opening the back window of your cap. Or worse: the Wolfman catches your scent, and you might as well have "eat me" written on those little piggies. Are you going to become just another statistic? Not on my watch. Caps are designed to lock from the outside — fine for protecting cargo, no good when the cargo is you. There's no man door with a lockable handle and deadbolt back there, so I built my own interior locks.
The Setup (and Why Keyless Isn't Enough)
My rig is a 2014 Ram 2500 with a 6.5-foot bed wearing a 2015 LEER 100RCC cap, with solid panel side doors and a left-and-right dual-handle back window. Some caps offer keyless entry on the back window, which would be ideal — unless the battery dies while you're locked inside. So I made everything lockable from inside, mechanically.
The Back Window: Brackets and Magnets
Each handle rotates 90°, swinging a metal arm behind the cap frame to hold the window. First I beefed up the cap frame with a piece of aluminum on each side. Then I fabricated aluminum brackets that slide over each locking arm in the secured position and snap into place with neodymium magnets. The front of the bracket slides under the gas cylinder mount, which physically prevents the arm from rotating to unlocked. Much more secure than the rope-or-chain anchors I've seen in other builds — the video shows exactly how I made them.
The Side Doors: Quick-Release Pins
I chose solid doors over glass — more secure, better insulated, and no curtains needed. The catch: the latch couldn't be turned with the handle in the closed position, so I removed the handle and trimmed each side until it could pivot freely. Then I made a locking bracket from two pieces of 1/8" aluminum plate bolted through the door frame with stainless hardware, drilled a 1/4" hole on each side of the latch, and now a quick-release pin drops in to lock the latch in place. Unlocking from inside takes two seconds: move the pin to the opposite hole. All the measurements are in the video.
A Word on Security
When people hear "security" they often think self-protection. If you go that route, research your rights carefully — the laws around defending yourself in a vehicle that can be driven away can differ from an RV hooked up at a campground. This video sticks to the part everyone can do: making sure the doors don't open unless you open them. It pairs well with the cab-to-cap pass-through that lets us reach the driver's seat without stepping outside.
Materials That Make It Work
As an Amazon Associate we earn from qualifying purchases. Using these links costs you nothing extra and helps support the channel — thank you!
Neodymium Magnets
What snaps the back-window brackets into place.
1/4" Quick-Release Pins
The two-second lock/unlock for the side doors.
1/8" Aluminum Plate
Bracket stock for both locking designs.
Build It Yourself
Watch the video for the close-ups and measurements before your next build session. And if you've ever had a scary encounter with a four-legged or two-legged creature while camping, tell us how you handled it in the video's comments — we read them all, and we'd love to learn from it.
Build smarter, sleep better
Every problem we solve on the Tramper becomes a video. Subscribe and skip the trial and error.
▶ Subscribe on YouTubeDisclaimer: The information provided in this article and its video is for entertainment/educational purposes only. By following any advice from this article, video, or any provided links, you do so at your own risk. Please consult with a professional before attempting any construction, plumbing or electrical work.