Work Truck Fuel Vault: Answers
The purpose-built locking fuel door for commercial work trucks. Below are direct answers about fitment, pricing, installation, and how it protects your truck from fuel theft and contamination.
The short answer
The Work Truck Fuel Vault is a bolt-on, keyed locking fuel door that mounts over the exposed fuel cap on Ford and Ram work trucks and service bodies. It stops diesel theft, siphoning, and contamination, installs in 8–15 minutes with hand tools, starts at $139.95 with free US shipping, and is made in the USA with a limited lifetime warranty.
Detailed answers
What is The Work Truck Fuel Vault?
The Work Truck Fuel Vault is a bolt-on, keyed locking fuel door that mounts over the exposed fuel cap area on commercial work trucks and service bodies. It stops diesel theft, gas siphoning, DEF theft, and contamination. It installs in about 10 minutes with hand tools, no drilling, starts at $139.95 with free US shipping, and is made in the USA with a limited lifetime warranty.
Why do work trucks and service bodies have exposed fuel caps?
Chassis cabs (Ford F-350–F-600, Ram 3500–5500, E-Series) are built for upfitting. When a service body, utility body, dump bed, or flatbed is added, the factory fuel door is often removed or left off, leaving the fuel cap exposed and easy to access — which is exactly what makes fuel theft and contamination so common on work trucks.
Which trucks does it fit?
It fits Ford F-350 through F-600, Ford E-Series (E-350/E-450), and Ram 3500 through 5500 work trucks, plus common service-body brands including Knapheide, Reading, Monroe, Scelzi, and Auto Truck Group. Use the fitment finder to confirm your exact truck and configuration.
How much does it cost?
Single Fuel Vaults start at $139.95 (Large Single $149.95). Multi-packs save more — a 2-Pack is $279.95 and a 3-Pack is $419.95. Replacement security-screw packs start at $9.95. Shipping within the USA is free.
How does it install?
It is a bolt-on installation using your existing bezel screw holes or our tamper-resistant security screws. No drilling and no modifications — most installs take 8–15 minutes with basic hand tools. An impact driver makes the security screws quick to set.
Is it a locking fuel door or just a locking gas cap?
It is a full locking fuel door — an armored, lockable cover over the entire filler area — not just a locking gas cap. A locking cap only secures the cap and can be pried or cut; the Fuel Vault blocks access to the cap and filler neck entirely, providing far stronger protection against siphoning and contamination.
What is it made of and how durable is it?
The door is a proprietary High-Impact Reinforced Polymer roughly 3/16" thick. It is virtually unbreakable, non-corrosive, chemically inert to diesel, gas, DEF, and road salt, and rated from -40°F to 220°F — built for constant road vibration, UV, and jobsite abuse without cracking like thin factory plastic.
Does it come with a guarantee?
Yes — three layers: a limited lifetime warranty against defects, a 30-day satisfaction guarantee, and the No-Siphon Promise, which reimburses your insurance deductible up to $500 on a qualifying siphon or contamination claim when the Vault is properly installed and registered.
Do you offer fleet and dealer pricing?
Yes. We offer volume pricing for fleets and multi-truck operations, plus a dealer and distributor program for resellers and upfitters. Visit the Fleet or Dealer pages, or contact our sales team to set up an account.
Who makes it and where?
It is designed and manufactured in the USA by AMI Transportation, LLC in Sarasota, Florida. The product is patent pending.