Your Fuel Cap Is Wide Open
Every Chassis Cab Ships Without a Fuel Cap Lock. We Fixed That.
You lock your tools, your cab, and your trailer. But your fuel cap? Completely exposed. The Work Truck Fuel Vault is the fuel cap lock that covers the entire filler area — not just the cap.
Founders Edition pricing — starting at $139.95 (Save up to $60)
An Unlocked Fuel Cap Is an Open Invitation
Work trucks carry 40–68 gallons of diesel. The fuel cap is the easiest access point on the entire vehicle — and it has zero protection.
- Chassis cab trucks have no factory fuel cap lock or fuel door
- Anyone can access the fuel filler in seconds without tools
- Diesel theft costs $500–$1,000 per incident plus morning downtime
- Fuel contamination from sugar, water, or debris destroys engines
- Locking gas caps provide minimal security — defeated in seconds
- Fleet fuel shrinkage adds up to thousands per year across multiple trucks
Lock It With an Armored Door
The Work Truck Fuel Vault is the fuel cap lock that fleet managers and contractors actually trust. Full coverage, real lock, bolt-on install.
- Armored locking door covers the fuel cap, filler neck, and access area
- Tumbler lock with security torx fasteners — tamper-resistant
- High-strength UV-stable composite built for outdoor commercial use
- Bolt-on in 8–15 minutes — no drilling, cutting, or modifications
- Fits Ford F-550, F-600, E-350, E-450, and Ram 5500
- Made in the USA — Sarasota, Florida
The Part The Factory Forgot
The Work Truck Fuel Vault is an armored, locking fuel door that covers the entire fuel access area on your work truck. No more exposed caps. No more easy targets.
Why Didn't This Exist Before?
Despite billions lost to fuel theft every year, nobody built a real solution for commercial work trucks. Here's why.
"Good Enough" Thinking
The industry defaulted to cheap aftermarket locking gas caps. A $15 key-locked cap was considered good enough — until thieves proved otherwise with a pair of pliers.
Upfitters Focus on the Body, Not the Cap
Manufacturers like Knapheide and Reading engineer every compartment lock on the service body — but the chassis fuel pocket belongs to Ford or Ram. Nobody owned the gap.
The Zero-Drill Engineering Problem
Consumer billet doors are made for flat pickup beds. The recessed fuel pocket on a commercial chassis is a completely different geometry — and drilling risks voiding the chassis warranty.
The Cost Was Just "Absorbed"
Fleets treated fuel theft like weather damage. A $500 siphoning hit got buried in operating expenses. Without a purpose-built product available, the problem was simply accepted.
The Work Truck Fuel Vault is the industry's first drop-in armored fuel door that uses existing factory mounting points. No drilling. No cutting. No warranty risk.
Who Needs a Fuel Cap Lock
Contractors
Lock the fuel cap on your service truck the same way you lock your tools.
Fleet Managers
Standardize fuel cap locks across every truck in your fleet.
Government
City and county fleets — lock every fuel cap with one purchase order.
Utility
Your trucks park in remote areas. Lock the fuel cap and sleep easy.
Upfitters
Include a fuel cap lock on every chassis cab build.
Owner-Operators
One truck, one fuel cap lock, done forever.
Chassis Compatibility
Purpose-built for the most popular commercial chassis platforms in the industry.
Ford
Super Duty & Commercial Chassis
- F-350 Chassis Cab
- F-450 Chassis Cab
- F-550 Chassis Cab
- F-600 Chassis Cab
- E-350 / E-450
- F53 Workhorse
Ram
Chassis Cab Heavy Duty
- Ram 3500 Chassis Cab
- Ram 4500 Chassis Cab
- Ram 5500 Chassis Cab
Our Guarantee
Limited Lifetime Warranty
Built to last. Warranted against defects in material and workmanship for the life of the vehicle on which it was originally installed.
30-Day Money Back
Not satisfied? Return within 30 days of receipt for a full refund. No questions asked.
Free Replacements
If your Fuel Vault is defective under normal use within the warranty period, we replace it at no charge.
Frequently Asked Questions
What is a fuel cap lock?
A fuel cap lock is any device that prevents unauthorized access to the fuel filler cap. Options range from locking caps ($15–$40) to armored locking fuel doors like the Fuel Vault ($139.95).
Why do work trucks need a fuel cap lock?
Commercial chassis cabs ship without any fuel security. The cap is completely exposed. A fuel cap lock prevents theft, siphoning, and contamination.
Is a locking cap enough?
For most work trucks, no. Locking caps are easily defeated with pliers. The Fuel Vault covers the entire fuel filler area with an armored door.
What trucks does the Fuel Vault fit?
Ford F-550, F-600, E-350, E-450, and Ram 5500 chassis cabs.
How does installation work?
Bolt-on in 8–15 minutes with basic hand tools. No drilling or cutting required.
How much does it cost?
Founders Edition starts at $139.95 with free shipping.
Is there a warranty?
Yes — Limited Lifetime Warranty and a 30-day money-back guarantee.
Lock Your Fuel Cap — Starting at $139.95
Armored fuel cap lock for Ford and Ram work trucks. Bolt-on. No drilling. Lifetime warranty.
Secure checkout • Free US shipping • No charge until your order ships