Our readers keep the lights on and my morning glass full of iced black tea. As an Amazon Associate, I earn from qualifying purchases.9 Best Auxiliary Gas Tank | Stop Running on Empty Mid-Job

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The Scepter Duramax is the most balanced portable fuel caddy on the market, combining a manageable 14-gallon capacity with a rugged high-density polyethylene shell that resists dents and UV radiation. The molded handle and 6-inch wheels make it genuinely easy to roll across gravel or a garage floor, and the 10-foot hose gives you reach without dragging the tank itself. It is designed as a gravity-feed system when elevated, and the included spout pump adds a manual dispensing option for lower positions.

Real-world owners consistently praise its durability—several report hoisting it onto hooks or shelves for gravity flow with zero leaks after months of use. The stiff hose and finicky pump lever lock are the most common friction points, but the tank itself holds fuel securely and the patented no-spill pump handle minimizes waste during transfers. Attaching a hand truck solves the stability issue when the tank is full and rolling over uneven surfaces.

For anyone who needs to refuel lawn mowers, ATVs, generators, or marine equipment without a heavy steel tank permanently mounted in a truck bed, this is the pick. Its 15-pound empty weight means one person can position it, and the yellow polyethylene will never rust. It is the definitive mid-range solution for light-to-medium duty cycles.

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VEVOR’s 35-gallon fuel caddy is a steel-bodied workhorse designed for users who need to move a meaningful volume of gasoline, diesel, or kerosene around a farm, shop, or marina. The bi-directional rotary hand pump lets you dispense or siphon fuel by reversing the cranking direction, and the 8.2-foot kink-free hose with nozzle provides a steady flow without electrical power. The anti-static ground clamp and mechanical fill gauge add operational safety and level visibility that smaller caddies often omit.

Owner feedback highlights the easy assembly—about 20 minutes out of the box—and the sturdy wheel setup, which includes 10-inch rear wheels and 2.5-inch front wheels for rolling over grass and gravel. Several owners use it to siphon and replace fuel in airplanes and tractors, confirming it works reliably when the pump is properly sealed with fuel-rated Teflon tape. The steel tank resists UV and dents better than plastic, but one long-term review reported bottom corrosion within a year, so adding a protective coating or storing it dry is wise.

This caddy occupies a middle ground: it is too heavy to lift into a truck bed easily when full (the tank weighs 50.7 pounds empty), but its wheeled frame and push handle make it ideal for ground-level refueling. It is the right choice for hobby farmers and equipment owners who want to store 35 gallons without committing to a permanent bed-mounted tank.

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The JohnDow JDI-FST15 is a UN/DOT-approved gravity-feed fuel station that prioritizes regulatory compliance and build quality. Its welded cold-rolled steel shell is rated for gasoline, diesel, and E85, and the 10-foot hose with integrated shut-off valve and squeeze handle makes dispensing simple. A ground wire with an alligator clip provides static dissipation—a critical safety feature that budget gravity tanks often skip. The tank is designed to be bolted to a trailer, flatbed, or secure surface, making it semi-permanent rather than portable.

Users consistently confirm that the gravity flow is fast and clean when the tank is mounted higher than the receiving vehicle’s filler neck. Several owners built custom carts for zero-turn mowers and side-by-sides, noting that the tank holds about 14 gallons of actual gasoline. The only notable limitation is that the outlet port is not at the very bottom of the tank, so you must tilt the unit to drain the last gallon. Shipping damage is a recurring complaint—the box often arrives ripped with dented ends—so inspect immediately upon delivery.

For someone who needs a certified tank for road transport between job sites or events, the JohnDow is the standout. Its 30-pound empty weight is manageable, and the heavy-duty welded construction means it will outlast cheaper steel tanks. The gravity system requires no pump maintenance, just elevation.

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The Better Built 29211584 is a 36-gallon rectangular diesel transfer tank designed to mount permanently in a pickup truck bed. Its alloy steel shell includes built-in baffles that add structural strength and prevent fuel slosh during transport, while the overfill restriction provides automatic shut-off at the pump nozzle to prevent spills during filling. The lockable vented cap adds basic security, and the flush-mounted 2-inch inlet and outlet bungs enable high-flow fuel transfers when paired with an aftermarket pump.

Owners love the space-saving footprint—11 inches wide by 17 inches high—which fits neatly in a truck bed without consuming excessive room. The glossy black finish looks clean on flatbed trucks, and the included mounting kit with rubber bushings isolates the tank from vibration. However, quality control is a recurring issue: multiple buyers report the tank arriving with bent mounting tabs, weld spatter inside the bungs, and missing hardware. A 2-inch NPT tap is recommended to clean out the ports before installation, and the paint is reportedly susceptible to chipping.

This tank is exclusively for diesel—the product description clearly states it is not for gasoline. If you need a compact, baffled diesel tank that sits low in the bed and can be plumbed into a 12V transfer system, it is a capable option. Plan to spend time addressing fit-and-finish issues out of the box.

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The VEVOR 48-gallon diesel tank is a polyethylene unit built for high-volume refueling, equipped with a 12V electric transfer pump that delivers a 10.6 GPM flow rate and an automatic shut-off nozzle. The duplex filtration system—an inner screen filter plus a premium outer filter—catches both large debris and fine particles, protecting your equipment’s fuel system. The integrated forklift pockets and molded grooves on top make this tank easy to load into a truck bed with a forklift or lift truck, and the lockable copper lid prevents tampering.

User reports emphasize that the pump primes easily and delivers fuel fast, but a thorough pre-flight inspection is mandatory. Several owners found the O-ring on the pump handle release was too stretchy for diesel and replaced it with a stiffer alternative. The fuel filter was finger-tight from the factory on some units, causing leaks until tightened. The mechanical fuel gauge is also noted as inaccurate, so it is better used as a rough reference than a precise measurement. Once these assembly issues are corrected, the tank performs reliably over months of use.

For a diesel equipment owner who needs to fill tractors, excavators, or semi-trucks without lifting 5-gallon cans, this tank offers the best flow-per-dollar ratio. The 55.5-pound empty weight is light enough for one person to load empty, and the orange color is highly visible on a job site.

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The VEVOR 58-gallon tank is the larger sibling to the 48-gallon model, using LLDPE (Linear Low-Density Polyethylene) with a wall thickness of 6mm that reaches 12mm at the thickest stress points. It retains the same 12V 140W transfer pump, 13.1-foot rubber hose, and duplex filtration system, but adds roughly 10 more gallons of usable capacity. The safety fill capacity is listed at 52 gallons with a maximum of 58, so buyers should treat the rating as an upper limit rather than usable volume.

Owner experiences mirror the 48-gallon version closely: the pump works well and the automatic nozzle prevents overfills, but fasteners commonly arrive loose, the internal filter may need cleaning of plastic shavings from the manufacturing process, and the rubber hose cannot fully fit inside the lid for storage, leaving it hanging out. One measurement-oriented buyer calculated the actual capacity at roughly 51.2 gallons, not the advertised 58. The forklift pockets again make loading into a truck bed straightforward for one person when the tank is empty at 65.5 pounds.

This is the best choice for someone who absolutely needs the largest possible polyethylene diesel tank with an integrated electric pump and is willing to spend the extra setup time tightening hardware and replacing the pump handle O-ring. The black color is more discreet than the orange 48-gallon version.

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The Dee Zee DZ92556NSB is a 42-gallon heavy-duty tank built from 14-gauge alloy steel, designed specifically for gasoline storage and truck bed mounting. It incorporates five internal stability baffles to control fuel movement during acceleration and braking, plus a radius curve design that eliminates weld pressure points for better structural integrity. The mounting tabs allow secure bolting to the truck bed floor, and the included drain plug simplifies periodic cleaning or water removal.

Owners using this tank in full-size pickups like the Ram 3500 dually report that it sits below the bed side rail, allowing a tonneau cover to close—except the fill cap protrudes above. The 59.5-inch width fits across standard truck beds, and the 19-inch height leaves clearance. Several users note that the mounting tabs arrived bent, which is a common shipping issue, but they were easily straightened with pliers. The 70-pound empty weight requires two people for installation. One long-term user uses it to refuel a fifth-wheel RV while towing, gaining 67 gallons of total capacity.

If you need a gasoline-rated tank that bolts directly into a truck bed and includes robust baffling for highway travel, the Dee Zee delivers durable construction and a 3-year limited warranty. It is not a portable caddy—this is a semi-permanent installation intended for vehicles that consume fuel faster than a standard tank can keep up.

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The RDS MFG INC 72771 is a 60-gallon aluminum transfer tank designed for diesel storage in truck beds, with a slim 12.75-inch height that allows it to fit under most tonneau covers. The aluminum construction—machined finish, no rusting—makes it a long-term investment for diesel owners who operate in humid or coastal environments. It includes a locking automotive-style fill cap and is listed as a universal fit for full-size trucks, though some vehicle-specific modifications may be required.

Owners confirm that the tank fits neatly under a bed cover on F-250 and F-350 models, extending total range to 110 gallons or more when combined with the factory tank. The installation is manageable with a helper, but the included install kit is sold separately, and the filler valve can be very difficult to access in tight spaces on Super Duty trucks. Filling through the 2-inch bung without an electric pump is slow—one user reported two hours to fill 57 gallons—so pairing this tank with a 12V transfer pump is strongly recommended. The capacity is also contested: the tank is rated at 60 gallons but some owners found actual fill volume closer to 50-57 gallons.

This tank is the premium choice for diesel truck owners who prioritize a corrosion-proof, low-profile installation that preserves bed space and bed cover functionality. The 91-pound empty weight is the heaviest here, so plan for two-person installation.

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The Dee Zee DZ91753 is the absolute heavy hitter of this lineup, offering a 106-gallon (advertised 110-gallon) capacity in a 0.125-inch Brite-Tread aluminum rectangle tank measuring 48x24x24 inches. The radius curve design reduces weld pressure points, and the included cap and coupler for venting allow it to be plumbed into a refueling system. Despite its massive volume, the aluminum construction keeps empty weight to just 100 pounds—light enough for a single person to slide in and out of a truck bed with some effort.

Long-term owners are emphatic about its durability: one 10-year update reports zero leaks, no corrosion, and only minor tarnishing on the aluminum surface after years of outdoor exposure in Florida humidity. The tank is light enough that a 120-pound user can move it when empty, and it eliminates the hassle of multiple fuel cans entirely. A key caveat: the tank is distinctly labeled that it is NOT an auxiliary tank for gravity feeding into a vehicle’s fuel tank, and it is not approved for gasoline transfer through the vehicle’s system—it is intended for pump-offloading into a storage tank or equipment. Diesel expansion in warm weather can cause overflow if the tank is filled near the top, so leave headroom.

This is the ultimate solution for diesel fleet operators, farmers with large equipment, or anyone who buys fuel in bulk and needs a legal, safe, and corrosion-proof storage tank. The price is an investment, but the per-gallon cost of aluminum storage this durable is hard to beat over a decade of service.