Fuel Door for Your Knapheide F-550
$80,000+ Truck • $15,000+ Knapheide Body • $0 Fuel Door
Your Ford F-550 with a Knapheide service body is a $95,000+ investment. Every Knapheide compartment locks. But the fuel cap on the F-550 chassis? Wide open. The Work Truck Fuel Vault adds the fuel door your Knapheide F-550 needs.
Founders Edition pricing — starting at $99.95 (Save up to $50)
$95,000+ Invested. Fuel Cap Wide Open.
You didn\'t buy a cheap truck or a cheap body. But the fuel security on your F-550 Knapheide combo is exactly $0 from the factory.
- Ford F-550 ships with a completely exposed fuel cap — no door, no lock
- Knapheide service bodies lock tools — but the fuel cap is on the Ford chassis
- F-550 Knapheide trucks carry 40–68 gallons of diesel — worth $200–$350
- Contractors and fleet managers leave their most expensive truck exposed
- The F-550 Knapheide combo is a prime target for fuel theft and siphoning
- No Ford dealer or Knapheide dealer offers a fuel door solution
The Fuel Door for Knapheide F-550s
The Fuel Vault is the armored locking fuel door purpose-built for the Ford F-550 chassis. It completes the security package on your Knapheide-equipped F-550.
- Armored door covers the entire F-550 fuel filler area
- Tumbler lock + security torx — matches Knapheide body hardware quality
- Purpose-built for the Ford F-550 chassis cab platform
- Zero interference with any Knapheide body configuration
- Bolt-on in 8–15 minutes — no drilling, no mods
- Made in the USA with Limited Lifetime Warranty
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.
F-550 Knapheide Owners Who Added a Fuel Door
Contractors
Your F-550 Knapheide service truck is your business. Lock the fuel.
Fleet Managers
Every F-550 Knapheide in the fleet gets a fuel door. Done.
Government
Municipal F-550 Knapheide trucks need fuel doors.
Utility
F-550 Knapheide utility trucks in remote areas — lock the fuel.
Ford/Knapheide Dealers
Add a fuel door to every F-550 Knapheide delivery.
Landscapers
F-550 Knapheide dump/chipper trucks — add a fuel door.
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
Does the Fuel Vault fit a Knapheide body on an F-550?
Yes. The Fuel Vault mounts to the Ford F-550 chassis at the fuel filler area. It fits perfectly alongside any Knapheide service body, utility body, or mechanics body installed on the F-550 chassis.
Why doesn't my F-550 with a Knapheide body have a fuel door?
The F-550 is sold as a chassis cab — an incomplete vehicle. Knapheide adds the service body but the fuel cap area is on the chassis, which Ford leaves completely exposed.
Will it interfere with the Knapheide body on my F-550?
No. The Fuel Vault mounts near the cab at the fuel filler neck. It does not touch or interfere with any Knapheide side compartments, doors, or panels.
What Knapheide body types on the F-550 does it work with?
All of them — KnapService, KUVcc, Utility, Forestry, Crane, Mechanics, Flatbed, and Dump bodies on the Ford F-550 chassis.
How does it install?
Bolt-on in 8–15 minutes with basic hand tools. No drilling, cutting, or modifications.
How much?
From $99.95 with free shipping.
Warranty?
Limited Lifetime Warranty and 30-day money-back guarantee.
Add a Fuel Door to Your F-550 Knapheide — Starting at $99.95
Locking fuel door for Ford F-550 Knapheide trucks. Armored. Bolt-on. No drilling. Lifetime warranty.
Secure checkout • Free US shipping • No charge until your order ships
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