Every Compartment Locks. The Fuel Doesn’t
Service Bodies • Contractor Bodies • Flatbeds
Royal service bodies lock everything but the tank. The Work Truck Fuel Vault is the missing piece on a Royal-equipped truck — an armored, locking fuel door that bolts on at the filler.
Founders Edition pricing — starting at $159.95 (Save up to $110 on the 3-Pack) · Security screws included
Royal Truck Body Locks the Tools — Not the Fuel
A Royal Truck Body body is built to secure tools and equipment. The fuel filler sits on the chassis, outside the body — and it ships unprotected.
- Royal service and contractor bodies leave the chassis fuel filler fully exposed
- Diesel and DEF are the only unlocked assets on a truck full of locked compartments
- Locking gas caps pop off with pliers in seconds
- Trucks sit overnight at jobsites and open yards where siphoning happens
- Contaminated fuel or DEF can sideline a truck and its crew
- Body builders can’t ship fuel security from the factory — it’s a chassis-side part
The Locking Fuel Door for Your Royal Truck Body Truck
The Work Truck Fuel Vault is an armored, locking fuel door that bolts on at the filler. It covers the whole fill area, not just the cap.
- Armored locking door covers the whole filler area, not just the cap
- Second door option for the DEF filler on diesel service-body builds
- Bolts on in 8–15 minutes — no changes to the Royal body
- Tamper-resistant security screws included with every door
- Easy add-on at upfit, delivery, or in the fleet shop
- Limited Lifetime Warranty and 30-day money-back guarantee
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.
Royal Truck Body Owners Who Need This
Contractors & Trades
Your Royal body locks the tools. Lock the diesel the same way.
Utility Crews
Service trucks that park remote overnight need the fuel locked too.
Upfitters & Dealers
Add it at upfit — a simple accessory with clear ROI for the buyer.
Fleet Managers
Standardize one door across every Royal-equipped truck in the fleet.
Municipal Fleets
City and county service bodies sit in open yards. Stop fuel shrink.
Equipment Rental
Protect fuel on trucks that change hands and jobsites every week.
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
Locking Fuel Cap vs. Fuel Vault
See how The Work Truck Fuel Vault compares to the alternatives.
| Feature | Locking Fuel Cap | The Work Truck Fuel Vault |
|---|---|---|
| Protection Type | Cap only | Full armored door over the fuel fill area |
| Tamper Resistance | Low — pliers remove in seconds | High — armored composite, security screws |
| Prevents Siphoning | Partial — hose can bypass | Yes — locked door blocks access |
| DEF Protection | Not included | Second door locks the DEF filler |
| Install Time | 1 minute screw-on | 8–15 min bolt-on (one time) |
| Warranty | None or 90 days | Limited Lifetime Warranty |
Feature comparison between standard locking fuel cap and The Work Truck Fuel Vault
Protection Type
Cap only
Full armored door over the fuel fill area
Tamper Resistance
Low — pliers remove in seconds
High — armored composite, security screws
Prevents Siphoning
Partial — hose can bypass
Yes — locked door blocks access
DEF Protection
Not included
Second door locks the DEF filler
Install Time
1 minute screw-on
8–15 min bolt-on (one time)
Warranty
None or 90 days
Limited Lifetime Warranty
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
Does the Fuel Vault fit Royal Truck Body builds?
Yes. Our fitment guide lists Royal service bodies on Ford F-350/F-550 and Ram 4500/5500 (Small door, two doors recommended for diesel plus DEF), Royal contractor bodies on Ford F-450/F-550 (one Small door), and Royal flatbeds on Ford F-350 through F-600 (one Small door).
Does it attach to the Royal body?
No. It mounts at the chassis fuel filler, so it works with the Royal body as built — no cutting or drilling into the body.
Why two doors on some Royal service bodies?
Diesel service-body builds usually have a separate DEF filler. A second door locks the DEF so it can’t be stolen or contaminated.
How long does install take?
About 8 to 15 minutes per door with basic hand tools. It bolts on — no welding and no changes to the body or chassis.
How much does it cost?
The Small door (WTFV-1001S) is $159.95 and the Large door (WTFV-1002L) is $169.95. A 2-pack of Small doors (WTFV-2001S) is $309.95. Tamper-resistant security screws are included with every door at no extra cost. UPS shipping is calculated at checkout. Fleet and dealer volume pricing is available.
Is there a warranty?
Yes — a Limited Lifetime Warranty and a 30-day money-back guarantee.
Are you affiliated with Royal Truck Body?
The Work Truck Fuel Vault is an independent aftermarket product. We are not affiliated with or endorsed by Royal Truck Body; the name is used only to describe fitment.
Lock the Fuel on Your Royal-Equipped Truck — Starting at $159.95
Armored locking fuel door. Security screws included. Bolts on in about 15 minutes. UPS shipping calculated at checkout.
Secure checkout • Live UPS shipping • No charge until your order ships
Royal Truck Body Fitment Guide
Door size and how many doors we recommend for each model.
| Model | Chassis | Years | Door Size | Doors | Notes |
|---|---|---|---|---|---|
| Service Body | Ford F-350 / F-550, Ram 4500 / 5500 | 2012–2026 | Small | 2 | Standard fit. |
| Contractor Body | Ford F-450 / F-550 | 2014–2026 | Small | 1 | Small door. |
| Flatbed | Ford F-350 through F-600 | 2012–2026 | Small | 1 | Fully exposed cap. |
The Work Truck Fuel Vault is an independent aftermarket product, not affiliated with or endorsed by Royal Truck Body. Brand names are used only to describe fitment.
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