Cummins Power. Zero Fuel Protection
6.7L Cummins Diesel • Up to 60 Gallons • Completely Exposed Fuel Cap
The Ram 5500 with the Cummins diesel is the heavy-duty workhorse of choice for contractors, utilities, and municipalities. It hauls, tows, and works harder than anything else on the road. But the fuel cap? Ram left it completely exposed. The Work Truck Fuel Vault locks what Ram forgot.
Founders Edition pricing — starting at $139.95 (Save up to $60)
Heavy-Duty Everything — Except Fuel Security
The Ram 5500 is built to work. The Cummins diesel drinks premium fuel. And the fuel cap has zero protection from the factory.
- Ram 5500 chassis cabs ship with completely exposed, unlocked fuel caps
- Cummins diesel fuel costs more — thieves know it and target Ram trucks
- Ram 5500s carry up to 60 gallons of diesel — that's $300+ worth of fuel sitting unprotected
- Service bodies, flatbeds, and utility builds leave the fuel cap easily accessible
- Locking gas caps are a token gesture — pliers remove them in seconds
- Ram 5500s work remote sites, construction zones, and fleet yards with minimal overnight security
Lock the Cummins Fuel on Your Ram 5500
The Work Truck Fuel Vault is the locking fuel door Ram should have included on every 5500. Purpose-built for the chassis. Works with every body type.
- Armored locking door covers the entire fuel filler area on your Ram 5500
- Works with every body — service bodies, flatbeds, dumps, cranes, utility, and more
- Bolt-on install in 8–15 minutes — no drilling, no cutting, no modifications
- Also fits Ram 3500 and Ram 4500 chassis cabs
- High-strength UV-stable composite built for heavy-duty environments
- 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.
Ram 5500 Owners Who Need This
Contractors & Trades
Your Ram 5500 service truck carries $50K+ in tools and 60 gallons of diesel. Lock the fuel the same way you lock the compartments.
Municipal Fleets
City and county Ram 5500 trucks sit in open yards overnight. Lock the diesel across every truck in the fleet.
Utility & Telecom
Ram 5500 utility trucks serve power, water, and telecom crews. Protect the fuel on trucks that work remote.
Ram Dealers
Add the Fuel Vault to every Ram 5500 delivery. The easiest accessory upsell with real customer ROI.
Fleet Managers
Eliminate fuel shrinkage across your Ram heavy-duty fleet. One part fits the 3500, 4500, and 5500.
Tow & Recovery
Ram 5500 rollbacks and wreckers park at tow yards. Lock the fuel between every call.
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 entire fuel access |
| Tamper Resistance | Low — pliers remove in seconds | High — armored composite, torx fasteners |
| Covers Fuel Filler Area | No — cap only | Yes — full hatch coverage |
| Prevents Siphoning | Partial — hose can bypass | Yes — sealed door blocks all access |
| Ram 5500 Specific Fit | Generic universal fit | Purpose-built for Ram chassis cab |
| Install Time | 1 minute screw-on | 8–15 min bolt-on (one-time, no drilling) |
| 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 entire fuel access
Tamper Resistance
Low — pliers remove in seconds
High — armored composite, torx fasteners
Covers Fuel Filler Area
No — cap only
Yes — full hatch coverage
Prevents Siphoning
Partial — hose can bypass
Yes — sealed door blocks all access
Ram 5500 Specific Fit
Generic universal fit
Purpose-built for Ram chassis cab
Install Time
1 minute screw-on
8–15 min bolt-on (one-time, no drilling)
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 my Ram 5500?
Yes. The Work Truck Fuel Vault is purpose-built for the Ram 5500 Chassis Cab. It mounts directly to the fuel filler area with no modifications to the truck or body.
Does it also fit the Ram 3500 and Ram 4500?
Yes. The Fuel Vault fits Ram 3500, 4500, and 5500 Chassis Cab models. All three share the same fuel filler configuration.
Why doesn't the Ram 5500 have a locking fuel door?
Ram sells the 5500 as a chassis cab — an incomplete vehicle. The fuel cap area is exposed because the body builder finishes the truck. Ram does not include any fuel security on chassis cab models.
Will it work with my Cummins diesel Ram 5500?
Yes. The Fuel Vault works with the Cummins diesel engine in Ram 5500 trucks. It protects the fuel filler area regardless of engine or fuel type.
Can I install it myself?
8 to 15 minutes with basic hand tools. No drilling, cutting, or special equipment required.
Does it interfere with my service body or flatbed?
No. The Fuel Vault mounts to the chassis at the fuel filler area near the cab. It does not interfere with any body configuration — service body, flatbed, dump, utility, or crane.
How much does it cost?
Founders Edition pricing starts at $139.95 with free shipping. Fleet and dealer volume discounts available.
Is there a warranty?
Yes — Limited Lifetime Warranty and a 30-day money-back guarantee.
Lock the Diesel on Your Ram 5500 — Starting at $139.95
The Cummins diesel deserves better than an exposed gas cap. Bolt-on locking fuel door. No drilling. Done in 15 minutes.
Secure checkout • Free US shipping • No charge until your order ships
Related Pages
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How to stop commercial diesel fuel theft.
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