Liquid transfer tanks are a staple upgrade of the work truck. Just like bed slides, roof racks, and crossover boxes, they’re an essential tool that helps make your truck more capable. In some cases, they might even be built into a combination unit featuring a liquid transfer tank and toolbox.
As the name implies, liquid transfer tanks are meant to help you transfer liquid. In some instances, it might simply be water; in others, it may be liquid needed for a job site, like fertilizers or chemicals. Many truck owners, however, use them to transport fuel, either to extend their own truck’s capacity or to refill other vehicles and equipment.
Obviously, these features make liquid transfer tanks incredibly useful, especially for those who spend long hours on the road, on the job site, or out in the field. But for many prospective buyers, the idea of installing a large tank in the bed of a truck brings up some anxiety. Understandably, since storing and transferring fuel and other chemicals can be dangerous if not done properly.
Truth be told, not all transfer tanks are created equal. Choosing the right one means understanding the differences—and making safety your top priority.
What Makes a Liquid Transfer Tank Safe?
The various properties of all the fluids you could possibly store in a liquid transfer tank are going to be the biggest determining factor in finding the one that best suits you. That doesn’t mean you need to be a chemist who knows everything about the fluid they’re working with down to the molecular detail and match it to a special tank design. Liquid transfer tank manufacturers have already hired those people to figure it out.
When deciding what tank you need, your best resource will be the product description. The manufacturer will clearly state what fluids their tanks are safe for use with. Whether it’s water, kerosene, diesel, or gasoline, they’ll let you know if the tank is good for it. Furthermore, you want to verify that the tank is actually DOT-approved, ensuring it's safe for use on the road.
Descriptions and legal stampings are only part of the safety equation when it comes to liquid transfer tanks. The other key factor? Build quality. After all, marketing copy can talk a big game—but it’s the materials and construction that matter most.
You really want to make sure you’re spending your money on a well-built tank that will last in the real world. Materials, welds, and especially the quality of the caps and fittings all need to be up to par. If you can, always take the time to look at a tank in person before you buy. It's best to look at multiple options, so you get a feel for what each manufacturer is bringing to the table.
How to Spot a DOT-Approved Transfer Tank
That DOT approval is a critical factor to keep in mind when shopping for a liquid transfer tank. It means the tank is legally approved for use on the roadways, which can save you a ton of trouble—legal or otherwise. Getting a DOT approval takes more than just slapping a sticker on the tank. To be compliant, a liquid transfer tank must meet specific safety and construction requirements, including:
• Corrosion-resistant construction – To withstand harsh environments
• Leak-proof seals and fittings – To prevent spills or leaks, even in the case of an accident
• Internal baffling – To reduce sloshing and improve stability during transit
• Proper venting systems – To relieve pressure and prevent vapor buildup
DOT-approved tanks are required to be clearly labeled, but it’s still wise to confirm. Reputable brands typically highlight DOT compliance in their product specs or manuals, but if you’re unsure—or buying from a lesser-known brand—ask the manufacturer for documentation verifying that the tank meets relevant DOT regulations.
You can also inspect the tank for features like baffling and venting systems. Just remember that not all safety standards are visible. When it comes to compliance, official documentation is more reliable than a quick visual check.
Safe Installation and Use
Installing a liquid transfer tank is relatively straightforward—especially compared to integrated systems like auxiliary fuel tanks. While installation typically involves drilling into the truck bed to secure the tank, transfer tanks are ultimately standalone units that operate via an external pump and don’t connect to your vehicle’s fuel system. This makes them a less permanent and more flexible option, as they can be removed or even transferred between vehicles if needed.
Proper mounting is still essential. Use high-quality, undamaged brackets, bolts, and washers, and take care when selecting a mounting location to avoid interfering with any fuel lines, brake lines, or electrical wiring beneath the bed.
On top of a proper install, here are some other best practices to keep in mind:
• Never modify your tank in a way that compromises its DOT approval or structural integrity. If the design doesn’t suit your needs, it’s safer to select a different model than attempt DIY alterations.
• Only use approved nozzles, caps, and fittings. These are designed to minimize the risk of spills and pressure-related failures.
• Don’t overfill. Flammable or volatile liquids expand, and overfilling can lead to leaks, spills, or dangerous pressure buildup.
Aluminum, Steel, or Poly?
When shopping for a liquid transfer tank, you’ll find three primary material options: aluminum, steel, and polyethylene. All three can make a great tank, and all three have a unique list of strengths and weaknesses. Choosing the right one depends on your needs, preferences, and budget.
Aluminum: Aluminum is probably the most well-rounded material for use in the construction of liquid transfer tanks. It's lightweight, durable, low maintenance, and naturally corrosion-resistant. However, aluminum tanks are more susceptible to dents and scratches, and they are generally more expensive than other options.
Steel: Steel has a lot of properties that make it great for use in liquid transfer tanks. Namely that it’s highly durable and more affordable than aluminum, which is why it’s such a popular choice. Unfortunately, steel tanks are heavy and can be more susceptible to corrosion over time, especially if not properly maintained.
Polyethylene: Poly tanks are a great option for buyers who need high corrosion resistance in a cost-effective solution. These tanks will not rust or corrode, and do not suffer from internal condensation. They’re also very lightweight, making them easy to move and install. While generally resistant to cracking or denting, they usually lack the impact-resistance of steel.
Find a Transfer Tank You Can Trust
When it comes to liquid transfer tanks, safety and compliance aren’t optional—they’re essential. That’s why it pays to invest in a tank from a trusted brand like RDS, Dee Zee, Titan, Transfer Flow, or UWS, all of which you can find right here on Parts Via.
Shop with confidence knowing you’re getting a tank built to perform—and take advantage of our fast, FREE ship-to-store option for added convenience. Whether you’re hauling fuel to the jobsite or out in the field, make sure you’ve