Grand Design Lineage on the Ford F-600?
“Lock Your Fuel Doors.”
The RV Fuel Vault is the only purpose-built locking fuel door for RVs — engineered to fit Super C motorhomes like the Grand Design Lineage built on the Ford F-600 chassis.
Use code GRANDDESIGN and save $10 per door
Why Grand Design Lineage Owners Swear By It
Your Lineage is a serious investment — but that exposed diesel fuel cap on the Ford F-600 chassis is left wide open. The RV Fuel Vault is the simple upgrade that finally puts that worry to rest.
Fuel Theft Protection
A tamper-resistant keyed lock stops siphoning and vandalism. No more worrying about your diesel at campgrounds or storage.
Contamination Defense
Seals your entire filler neck area against water, road grime, sugar, and contaminants that cause expensive repairs.
Factory-Finished Look
Covers that ugly exposed fuel cap with a clean, professional finish that complements your Lineage. The part the factory forgot.
8–15 Minute Install
No drilling, no cutting, no body mods. Bolts on over your existing filler neck with basic hand tools.
Lifetime Warranty
High-strength UV-resistant polymer built to last. Backed by a Limited Lifetime Warranty.
Free Shipping
Ships from our Missouri facility. Free standard shipping on every order. Made in the USA.
See the Difference
This is what the Lineage rolls off the lot with: an exposed, unprotected fuel cap. The RV Fuel Vault changes that.
❌ Before — Exposed & Vulnerable
✅ After — Locked & Protected
Built for Your Super C — and Every RV You Own
Engineered for Super C motorhomes like the Grand Design Lineage on the Ford F-600, the RV Fuel Vault also fits every other major RV type. Use the fitment finder to confirm your exact model.
Super C Motorhomes
Grand Design Lineage on Ford F-600 & more
Class A Motorhomes
Ford F53, Workhorse chassis & more
Class C Motorhomes
Ford E-350/E-450, F-550/F-600 & more
Class B Campervans
Ram ProMaster, Ford Transit & more
Toy Haulers
Fuel cap protection for your hauler
Fifth Wheels & Trailers
Protect the truck that tows your rig
Grand Design Lineage Discount: $10 Off Per Door
Use code GRANDDESIGN at checkout — or just order through this page and it's applied automatically.
Free shipping • 30-day satisfaction guarantee • Limited Lifetime Warranty
From one RV owner to another:
“I added these to my own rig and honestly wish they came standard. That exposed fuel cap always bugged me — it's a security risk, a contamination risk, and it looks unfinished. The RV Fuel Vault fixed all three in about ten minutes. If you camp, travel, or store your RV like I do, do yourself a favor and get one.”
— A fellow RV owner & RV Fuel Vault partner