Lock Your Fuel.
It’s That Simple.
This is a real work truck with the Work Truck Fuel Vault bolted on. One armored, keyed door covers the exposed fuel filler that thieves love — and shuts down diesel theft, gas siphoning, and DEF contamination for good.
What You’re Looking At
Three things, one simple result: a truck whose fuel can’t just be walked off with.
The badge
The Work Truck Fuel Vault badge — the bear in the hard hat guarding the lock. It marks a truck whose fuel is protected.
The message
“Lock Your Fuel. It’s That Simple.” No apps, no subscriptions, no complicated hardware — just a locked door over your fuel.
The armored door
The bolt-on locking Fuel Vault, covering what used to be an exposed filler and cap. This is the whole product, installed and working.
An exposed cap
- The upfit removed the factory fuel door — the cap sits out in the open.
- A siphon hose or a hand tool is all it takes to drain the tank.
- Trucks left at yards, job sites, and curbs overnight are easy targets.
- Every empty tank is a late start and a crew standing around.
A locked door
- Armored, keyed door covers the entire fuel and DEF filler area.
- A visible deterrent that sends thieves looking for an easier truck.
- Bolts on in 8–15 minutes with hand tools — no drilling.
- Made in the USA and built to take years of jobsite abuse.
Why It’s That Simple
No apps. No subscriptions. No wiring. Just a door and a key.
Bolt it on
Hand tools, about 8–15 minutes per truck, no drilling.
Turn the key
The filler and DEF cap are now locked behind an armored door.
Fuel locked
Siphoning and drive-off theft stop at the easiest point of attack.
What Fleets See
Fuel loss dropped to near zero across the yard
A regional public-works fleet outfitted 30-plus F-550 and Ram 5500 chassis after repeated overnight siphoning at an unsecured lot. Reported fuel shrinkage fell off almost immediately after the bolt-on doors went on.
Stopped repeat siphoning at remote job sites
A utility contractor running trucks parked at remote and unsecured sites installed doors fleet-wide. The exposed fuel and DEF caps were the weak point — once covered, the repeat losses stopped.
Paid for itself inside the first month
A grading contractor lost several hundred dollars of diesel from a single truck before protecting the fleet. At roughly the cost of one tank of stolen fuel per truck, the doors paid back fast.
Added as a standard buildout upgrade
A service-body upfitter now offers the locking fuel door as a visible security line item during buildout, giving fleet buyers a factory-finished theft deterrent from day one.
Illustrative, industry-representative scenarios. Individual results vary by fleet and operating conditions.
Questions About This Install
What is in this photo?+
This is a real commercial work truck with the Work Truck Fuel Vault installed. The black armored panel below the badge is the bolt-on locking fuel door, covering the exposed factory fuel filler and cap. Above it are the Work Truck Fuel Vault badge decal and our “Lock Your Fuel” sticker. Nothing was staged — this is how the door looks bolted onto a working truck.
Why do work trucks need a locking fuel door?+
On most chassis-cab work trucks the factory fuel door is removed during the service-body or flatbed upfit, leaving the fuel cap exposed and easy to reach. That open filler is an invitation to siphon hoses, drive-off theft, and DEF contamination. An armored locking door covers the whole opening so the fuel and DEF fillers are no longer sitting in the open.
How does the Work Truck Fuel Vault install?+
It bolts on in about 8–15 minutes with hand tools — no drilling and no cutting. The door mounts over the existing filler area using the included security hardware, then locks with a key. Because there is no drilling, it does not affect the vehicle body warranty.
Does it really stop fuel theft?+
No lock is uncrackable, but a visible armored door is a strong physical and psychological deterrent. Thieves target the easiest trucks, and an exposed cap is the easiest of all. Covering the filler with a keyed steel-reinforced door sends them looking elsewhere and blocks casual siphoning outright. It pairs well with fuel-card controls and telematics for a complete program.
What trucks does it fit?+
It fits Ford F-350 through F-600, Ford E-Series, and Ram 3500 through 5500 chassis, plus common service-body and flatbed configurations. If you run a mixed Ford and Ram fleet, we map the correct part numbers so one order covers your whole fleet.
Ready to lock your fuel?
Order for one truck or price out a whole fleet. Tell us your chassis mix and we’ll match the right part numbers.