How do I stop fuel theft and siphoning on my RV?
By The RV Fuel Vault, Sarasota, Florida · Updated October 2026
Short answer
The most effective step is to lock the fuel fill itself. Most motorhomes leave the factory with a bare, exposed fuel cap that anyone can open in seconds. The RV Fuel Vault bolts a keyed door over the fill so a siphon hose cannot reach the cap. Pair it with lit, watched parking, keeping the tank topped off only when you are with the coach, and checking the fill after storage.
Check my RV in Find My Fit5 steps that work
1. Lock the fill with a door made for your chassis (RV Fuel Vault, from $159.95). 2. Park in lit, camera-covered spots and avoid isolated rest-area corners overnight. 3. In storage lots, park the fill side against a wall or fence when possible. 4. Check your fuel gauge and the fill area after every storage period. 5. Report theft to police and your insurer. Registered RV Fuel Vault owners are covered by the No-Siphon Promise, which reimburses your insurance deductible up to $500 if fuel is siphoned through a properly installed door.
Why RVs are targeted
A motorhome tank holds 40–100+ gallons, far more than a car, and RVs sit unattended for days at campgrounds and months in storage. Exposed caps make it quick and quiet.
Related questions
Do anti-siphon screens work on RVs?
Many RV filler necks are not designed for screens, and a screen does nothing to stop contamination. A locking door covers the fill completely.
Does it also stop contamination?
Yes. With the fill enclosed, nobody can add sugar, water or debris to the tank.
Learn more
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