Heavy-Duty Bodies. Unprotected Fuel Fill
CV Series • MV Series • HV Series • DuraStar 4300
International CV and MV Series trucks pair heavy-duty bodies with an unprotected fuel fill. The Work Truck Fuel Vault bolts straight on — and a second door locks the DEF on CV, MV and HV builds.
Founders Edition pricing — starting at $159.95 (Save up to $110 on the 3-Pack) · Security screws included
International Builds the Truck — Not the Fuel Lock
International commercial trucks leave the factory as incomplete chassis. The body builder finishes the truck, and nobody adds a lock to the fuel filler.
- CV, MV and HV Series trucks leave diesel and DEF fillers exposed
- Dump and plow trucks sit in open yards between storms and jobs
- Legacy DuraStar 4300 fleets have no fuel security at all
- Locking gas caps come off with pliers
- DEF contamination can derate a truck mid-season
- Fleet fuel loss hides inside fuel card totals
The Locking Fuel Door for Your International 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 over the diesel filler
- Second door locks the DEF filler on CV, MV and HV
- Small door for CV Series; Large door for MV, HV and DuraStar 4300
- Bolt-on install in 8–15 minutes
- Tamper-resistant security screws included with every door
- 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.
International Owners Who Need This
Public Works & DOT
HV dump and plow trucks park in open yards — lock fuel and DEF.
Construction
MV and HV dump bodies sit at jobsites with full tanks.
Utility Fleets
CV and MV service and bucket trucks work remote sites.
International Dealers
A fuel-security add-on at upfit or delivery.
Delivery Fleets
MV box trucks park overnight between routes.
Legacy Fleets
DuraStar 4300 trucks still on the road get a simple upgrade.
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
Which International trucks does it fit?
Our fitment guide lists the CV Series (Small door, two recommended for diesel plus DEF), MV Series and HV Series (Large door, two recommended), and the DuraStar 4300, 2010–2019 (one Large door).
Why does the CV Series take the Small door?
The International CV shares GM 4500/5500 architecture, so it uses the same Small door as the Silverado and Sierra 4500HD/5500HD.
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.
Lock the Diesel and DEF on Your International — 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
International Fitment Guide
Door size and how many doors we recommend for each model.
| Model | Years | Door Size | Doors | Notes |
|---|---|---|---|---|
| CV Series | 2019–2026 | Small | 2 | Shares GM 4500/5500 architecture. |
| MV Series | 2018–2026 | Large | 2 | Large door. |
| DuraStar 4300 | 2010–2019 | Large | 1 | Legacy fleets still running. |
| HV Series | 2018–2026 | Large | 2 | Dump and plow builds. |