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Questions? Call or Text our US based team: 800-964-5341
Questions? Call or Text our US based team: 800-964-5341

Transfer Flow Low Profile Under Tonneau Auxiliary Fuel Tank

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Questions? Call our US Based team: 1-800-964-5341 (9am-9pm; 7days a week)

Original price $1,745.26 - Original price $1,870.62
Original price
$1,745.26
$1,745.26 - $1,870.62
Current price $1,745.26

1 week estimated lead time

Ask a Question / Check Current Lead Times

The low profile Transfer Flow auxiliary fuel tank is designed to fit under tonneau covers.  Choose from 40 or 50 gallon sizes. Either option offers minimal height designed to fit comfortably underneath your tonneau cover. 

The Transfer Flow In-Bed auxiliary fuel tank is designed to be compatible with almost any diesel truck, including half-ton pickups, trucks with utility beds, RamBox equipped trucks, or those with a factory installed 5th wheel prep package or other 5th wheel hitch.

The patented fuel tank design has a recessed cover box where the sending unit, rollover valve, and fuel filter come preassembled. You'll be pleased that its low height means it can fit under most standard tonneau bed covers.

This auxiliary system is computer-controlled by the patented TRAX 4™ operating system with exclusive AutoTrans® technology. Computer-controlled automatic fuel transfers mean worry-free operation, and much safer and more reliable operations than gravity fed systems.

Want to know the status of your on-board fuel systems? Simply download the TRAX 4™ app to your smart phone and enter your vehicle and fuel system information. In no time, you’ll be able to monitor your pickup’s fuel capacity! During fuel transfer, the message “PUMP ON” will be displayed. You also have the option of displaying either the gallons or the percentage of fuel in each tank.

If you prefer not to use the TRAX 4™ app with your auxiliary tank but still want to know how much fuel you have, Transfer Flow offers an in-cab fuel level monitor LCD. The LCD shows the fuel level of the auxiliary tank with an easy-to-read bar graph that decreases when fuel is transferred to the pickup’s main fuel tank. This item is sold separately.

Built from ReliaSteel®, high-yield U.S. aluminized steel; and powder coated black, TFI tank systems offer superior corrosion resistance and strength.

Sizes:

  • 40 Gallon - 48 inches long x 19 inches wide x 19.38 inches high.
  • 50 Gallon - 60.75 inches long x 18.5 inches wide x 18.25 inches high.

Notes:

  • The 40 gallon size includes a fill neck located at the top front corner of the tank.
  • The 50 gallon size includes a fill neck located at the top of the tank. The 2.5 inch fill neck is included in the 18.25 inch total height of the 50 gallon tank. 

Fits:

  • 40 Gallon 2008-22 Ford, 2010-22 GM, 2010-22 Dodge/Ram
  • 50 Gallon -  2008-22 Ford, 2010-22 GM, 2010-22 Dodge/Ram 

FEATURES

  • Recommended for drivers who require additional fuel capacity but require a small footprint to maximize available bed space for 5th wheel hitches, Rambox beds, and cargo.
  • Won't interfere with standard 5th wheel hitch.
  • Fits under most tonneau bed covers.
  • Robot-welded seams provide extraordinary strength, unlike rotationally molded plastic tanks or cheaper steel brands.
  • Fuel tank systems include all components needed for installation.
  • TRAX 4™ computer-controlled automatic fuel transfers for worry-free operation with exclusive AutoTrans® technology.
  • Built from ReliaSteel®, high-yield U.S. aluminized steel powder coated black for superior durability and strength.
  • Baffled to prevent fuel sloshing.
  • 6 year, unlimited mile warranty.
  • Made in the USA.

Other Auxiliary Tank Options:

What are your tanks made from?

Transfer Flow tank systems are crafted with 12- and 14-gauge ReliaSteel®, high-yield U.S. aluminized steel (powder coated for a longer lasting, durable finish), or aluminum diamond plate.

Aluminized steel is steel that has been electroplated with aluminum at the steel manufacturers. By electroplating the steel with aluminum, it acts as a corrosion resistant material. It’s the same material we have used for more than 35 years for our aftermarket and OEM fuel tanks!

Why are Transfer Flow Tanks Expensive?

Our mission is to support our customers, community, and country by engineering and manufacturing premier quality “Made in the USA” fuel systems and vehicle accessories. Transfer Flow fuel tanks are made in America, by hard-working Americans, using only the finest U.S. materials and production equipment. Keeping our products premier and American-made is costly, but we firmly believe in the value and integrity of American craftsmanship.

Will I void my vehicle's warranty if I install a Transfer Flow tank?

No, using Transfer Flow fuel tanks will not void the vehicle’s warranty. The Magnuson-Moss Warranty – Federal Trade Commission Improvement Act of 1975 protects consumers from such fraudulent activity by new car dealers. Under this Act, aftermarket equipment that improves performance does not void a vehicle manufacturer’s original warranty, unless the warranty clearly states the addition of aftermarket equipment automatically voids your vehicle’s warranty or if it can be proven that the aftermarket device is the direct cause of the failure. The easiest way to check this is to look in your owner’s manual under, “what is not covered”. Under Magnusson-Moss Act a dealer must prove, not just vocalize, that aftermarket equipment caused the need for repairs before they can deny warranty coverage. If they cannot prove such a claim or offer an explanation, it is your legal right to demand compliance with the warranty. The Federal Trade Commission administers the Magnusson-Moss Act and monitors compliance with warranty law.

Can I use a Transfer Flow tank in conjunction with another after market fuel tank?

No, Transfer Flow fuel tanks are never to be used in conjunction with fuel tanks made by other aftermarket fuel tank manufacturers.

Does Transfer Flow sell gravity feed systems?

No, Transfer Flow does not offer a gravity flow system.

Are Transfer Flow tanks DOT approved?

Yes, Transfer Flow refueling tanks have received a special permit from the Department of Transportation to carry and transfer gasoline, diesel, ethanol, methanol, kerosene, and aviation fuel. See accompanying tank materials for DOT stipulations and decals.

Does Transfer Flow sell fuel tanks for gasoline vehicles?

Transfer Flow manufactures and sells DOT-legal refueling tanks that are approved to carry and transfer gasoline, as well as diesel, ethanol, methanol, kerosene, and aviation fuel.

Will a high capacity replacement tank affect my truck's stock fuel gauge and trip computer?

Your stock fuel gauge will read accurately when our high-capacity replacement tank is installed on your vehicle. When your gauge reads half full, you have approximately half tank of fuel. Most functions on your truck’s trip computer should work properly, except for the miles-to-empty feature. This feature will continue to read fuel levels as though you still have the stock tank installed.

Will I need to purchase additional parts to install a Transfer Flow tank?

No! When you order a Transfer Flow fuel tank system, you can rest easy knowing that you will receive a complete system with comprehensive step-by-step instructions and every part required for installation, down to the last zip tie! All high-capacity replacement tanks include mounting straps for secure underbody installation.

What is the difference between Transfer Flow TRAX operating system versions?

TRAX-UFS (1998–2004)

Trax-UFS was Transfer Flow’s first patented computer-controlled system for auxiliary tanks. This system came with auxiliary fuel tank, in-line pump, auxiliary sending unit, wire harness, computer module, installation kit, and dash-mounted LCD. It removed the need to manually toggle between main and auxiliary fuel tanks and automatically transferred fuel into the main fuel tank.

EXPRESS-UFS (2005–2011)

The EXPRESS-UFS auxiliary system came pre-assembled with the 70-gallon in-bed auxiliary fuel tank. This system included an auxiliary fuel tank, an auxiliary fuel pump, all mounting hardware, wire harness, fuel lines, and computer module. The computer module for this system was located with the tank unit and did not come with a dash-mounted display. In 2009, Transfer Flow redesigned all auxiliary tanks to use the EXPRESS-UFS system.

TRAX-II (2004–2013)

The TRAX-II system was the second patented computer-controlled system for auxiliary tanks. TRAX-II incorporated the computer module into the dash-mounted display and improved the transferring process from TRAX-UFS. This system included an auxiliary fuel tank, auxiliary fuel pump, all mounting hardware, fuel lines, and the computer module with LCD.

MAXFLO-TFI (2013–2015)

The MaxFlo-TFI module allowed for automatic fuel transfers from the auxiliary tank to the main tank. This version of the computer-controlled system did not come with a dash-mounted display or switch. The system did have an optional upgrade to include a small dash-mounted digital lightbar that displayed fuel level in the auxiliary tank only.

Can I install a Transfer Flow tank myself?

Yes, you sure can! We include comprehensive step-by-step installation instructions with all Transfer Flow fuel tank systems. We also have installation videos on our YouTube channel for visual reference.

Want your tank installed by someone else? Call us to schedule an installation appointment at our facility in Chico, California. If that’s too far of a drive for you, we have more than 325 qualified installers across the U.S. and Canada that can install your Transfer Flow tank and get you ready for adventure!

Estimated Product Handling: 2 to 3 days

After placing an order, customers have up to 48 hours to cancel the order unless the item has been crated and/or shipped.

Orders for large or heavy items ship via a trucking carrier. Freight delivery is typically 2 to 6 business days, allow extra time for remote locations.

The Freight Carrier or Tucking company will contact you to set up an appointment time before delivering.  Once your product leaves our warehouse, we will send you an email with a link to the freight carrier’s website and the tracking number. Tracking numbers take 1 business day to update.

Package Inspection

Please inspect your package upon delivery. If there is obvious damage, please note the damages on the delivery receipt. Contact us within 24 hours to report the damage, by either e-mail or phone. Please retain all original boxes and packaging.

Returns (Applies to Transfer Flow products only)

  • All returns must be pre-authorized and require a return authorization.  Please email sales@tankretailer.com to request a return authorization.  
  • Returns are accepted for brand new and unopened products only.  No products may be returned after installation or attempted installation.
  • All returns must be requested within 30 calendar days from the delivery date.
  • The product must be in the original packaging and include all packaging materials, crates, boxes, and pamphlets.
  • All returns include a 25% restocking fee.
  • Customers are required to pay for the cost of return freight shipping.
  • The final return amount will be calculated as the Purchase Price less return shipping cost less the 25% restocking fee.

Transfer Flow fuel systems and parts are covered by a six-year unlimited mile warranty against defects in material and workmanship throughout the U.S. and Canada from the unit purchase date by the original purchaser for the original vehicle the unit was installed in.

Warranty will not apply when product failure is caused by conditions beyond the control of Transfer Flow, such as:

  • Malfunction due to incorrectly ordered product
  • Damage from misuse, negligence, or failure to provide reasonable and necessary maintenance
  • Damage caused by improper installation
  • Damaged caused in shipment or improper handling
  • Damage caused by contaminated fuels or fuel additives
  • Product modification or alteration
  • Products made from pickled and oil material are not covered under warranty for corrosion

Any action against Transfer Flow for breach of the warranty must be commenced within one (1) year after the cause of action has accrued.

Any action against Transfer Flow for breach of the warranty must be commenced in the Superior Court of Butte County, State of California.

For specific information regarding part exceptions, exclusions and limitations, warranty claim procedures, and federal regulatory provisions, please read our full warranty details below.

1. SIX YEAR/UNLIMITED MILE WARRANTY

TRANSFER FLOW, INC. (“TFI”) fuel systems and parts are - EXCEPT AS NOTED IN PARAGRAPHS 2, 3, AND 4 BELOW - covered by a six-year unlimited mile warranty against defects in material and workmanship. This warranty is in effect in the United States and Canada from the date the unit is purchased by the Original Purchaser (“Original Purchaser” shall mean the person who purchases for his own use and “Original Vehicle” shall mean the vehicle for which the unit is originally purchased).

2. SPECIFIC PARTS WARRANTY

Specific parts purchased from TFI are warranted against defects in material and workmanship as follows:

  • Part number 070-TK-34310 is covered by a one-year warranty from the date of purchase by the Original Purchaser for the Original Vehicle (AND IS TO BE USED FOR DIESEL FUEL ONLY). This refueling tank is only compatible with a GPI® or Fill-Rite® 15-GPM refueling pump (Transfer Flow part number 070-FU-34415 or 070-FU-34417). The tank warranty will be void if another fuel pump is used in conjunction with this tank.
  • Part number 070-TK-34311 is covered by a one-year warranty from the date of purchase by the Original Purchaser for the Original Vehicle (AND IS TO BE USED FOR DIESEL FUEL ONLY). This refueling tank is only compatible with a GPI® or Fill-Rite® 15-GPM refueling pump (Transfer Flow part number 070-FU-34415 or 070-FU-34417). The tank warranty will be void if another fuel pump is used in conjunction with this tank.
  • Sending units are covered by a two-year warranty from the date of purchase by the Original Purchaser for the Original Vehicle.
  • 12-volt refueling pumps are covered by a two-year warranty from the date of purchase by the Original Purchaser for the Original Vehicle (AND ARE NOT TO BE USED FOR AVIATION FUEL).
  • 6 PSI pumps are covered by a two-year warranty from the date of purchase by the Original Purchaser for the Original Vehicle.
  • Fuel gauges are covered by a two-year warranty from the date of purchase by the Original Purchaser for the Original Vehicle.
  • TRAX components, when purchased separately, are covered by a 90-day warranty from the date of purchase by the Original Purchaser for the Original Vehicle.
3. EXCLUSIONS AND LIMITATIONS

THE TFI WARRANTY, DESCRIBED IN PARAGRAPHS 1 AND 2 ABOVE, IS SUBJECT TO THE FOLLOWING EXCLUSIONS AND LIMITATIONS:

  • The rights of the Original Purchaser under the TFI warranty are LIMITED to return of the goods and repair or replacement of nonconforming goods.
  • THIS WARRANTY DOES NOT COVER INCIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING, BUT NOT LIMITED TO: LOSS OF USE OF THE WARRANTED PRODUCT, LOSS OF TIME, INCONVENIENCE, TRANSPORTATION EXPENSES, TOWING, EXPENSES FOR TRAVEL, LODGING, TELEPHONE AND GASOLINE, LOSS OR DAMAGE TO PERSONAL PROPERTY OR LOSS OF REVENUE. NOTE: SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THE ABOVE LIMITATION OR EXCLUSION MAY NOT APPLY TO YOU.
  • Warranties will only cover products on which the identification label is affixed; if the label has been removed or defaced, the warranty is no longer valid.
  • TFI fuel systems are compatible with a maximum 20% concentration of biodiesel fuel manufactured ASTM D7467 specifications. Concentrations above 20% or failing to comply with ASTM D7467 specifications will void warranty.
  • THE WARRANTY PROVIDED IN PARAGRAPHS 1 AND 2 ABOVE IS EXCLUSIVE AND IS IN LIEU OF ALL OTHER WARRANTIES (EXPRESS, IMPLIED, OR OTHERWISE) INCLUDING, BUT NOT LIMITED TO, ANY WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN THE EVENT IMPLIED WARRANTIES MAY NOT BE EXCLUDED, THE TERM OF ANY IMPLIED WARRANTY SHALL NOT EXCEED THE TERM OF THE APPLICABLE EXPRESS WARRANTY PROVIDED IN PARAGRAPHS 1 AND 2 ABOVE. SOME STATES DO NOT ALLOW LIMITATIONS ON HOW LONG AN IMPLIED WARRANTY LASTS, SO THE ABOVE LIMITATION MAY NOT APPLY TO YOU.
  • The warranty will not apply when product failure is caused by conditions beyond the control of TFI, such as:
  • Products made from pickled and oil material are not covered under warranty for corrosion.
  • The in-line fuel filter provided with the TFI fuel system is not covered by warranty as it is a standard maintenance item.
  • Any action against TFI for breach of the warranty must be commenced within one (1) year after the cause of action has accrued.
  • Any action against TFI for breach of the warranty must be commenced in the Superior Court of Butte County, State of California.
4. WARRANTY CLAIM PROCEDURES
  • If you have difficulty with your fuel system, consult the dealer where the unit was originally purchased. Your dealer will then contact TFI and request assistance. TFI will require model, part and serial numbers, proof of purchase, and date of installation. TFI reserves the right to examine the claimed defect in the field or upon return of the tank or component to TFI’s facility with all shipping charges being prepaid. If a part is defective and must be replaced, TFI will provide a Returned Merchandise Authorization (“RMA”) number, authorization, and instructions for replacement or further handling.
  • No payment will be made for parts purchased or repaired in the field without prior authorization by TFI.
  • TFI will pay its established warranty labor rates to service points or service dealers who have service agreements with TFI.
  • If an item is shipped as a replacement for a defective part, a charge will be made for this part. Credit will be considered upon return of the defective item. ALL RETURNED ITEMS MUST BE IDENTIFIED WITH THE RMA NUMBER AND RETURNED WITHIN 30 DAYS OF OPENING THE CLAIM.
5. FEDERAL REGULATORY PROVISIONS

This warranty gives you specific legal rights, and you may also have other rights which vary from State to State, and in accordance with specific federal regulations. TFI does not authorize any person to create for TFI any other obligation or liability in connection with TFI fuel systems. If TFI fails to successfully perform its obligation under this warranty, the Original Purchaser has available the remedies provided by the Magnuson-Moss Warranty Act (P.L. 93-637) and any applicable state law.