aluminum tank industries|SKU:AUX80L-var-55999-c7ea54

ATI 80-Gallon L-Shaped Auxiliary Diesel Fuel Tank

80-Gallon Diesel Range Extension for Toolbox-Equipped Trucks

80-gallon fuel capacity — Extends driving range between fuel stops
L-shaped tank design — Fits under standard crossover toolboxes
5th wheel compatible — available for most 5th wheel hitches
Aluminum tank construction — Lightweight, corrosion-resistant build
Fuel Shotz compatible — Connects through factory filler neck
  • FREE Freight -- LTL delivery to your site — call for liftgate options
  • FREE Pre-offer Spec Review -- We verify fitment and compatibility before you order

$855.88

30-day money back · No restocking fee

🔒 100% Secure Checkout

Visa Mastercard American Express Apple Pay Google Pay Klarna Link by Stripe
Free Returns 30-day hassle-free returns.
Free Delivery Every order, every time.
Ships in 3–5 Days Heavy-duty crating included.
4.9/5 Stars 2,400+ verified reviews.

In the box

  • ATI 80-gallon L-shaped aluminum auxiliary tank
  • Fill neck assembly
  • Mounting tabs
ATI L-Shaped Auxiliary Fuel Tank
ATI 80-Gallon L-Shaped Auxiliary Diesel Fuel Tank
$855.88

80-Gallon Diesel Range Extension for Toolbox-Equipped Trucks

Increase your driving range with the ATI 80-gallon L-shaped auxiliary diesel tank. Built-to-spec from aluminum, this tank fits under most crossover-style toolboxes and provides available for 5th wheel applications. The field-proven design connects directly to your factory fuel tank via the ATI Fuel Shotz system, keeping your factory tank full until the auxiliary is empty. When your factory gauge drops from full, it is time to refuel. Ships free.

FREE SHIPPING30-DAY RETURNSEXPERT SUPPORTFREE SHIPPING30-DAY RETURNSEXPERT SUPPORTFREE SHIPPING30-DAY RETURNSEXPERT SUPPORTFREE SHIPPING30-DAY RETURNSEXPERT SUPPORTFREE SHIPPING30-DAY RETURNSEXPERT SUPPORTFREE SHIPPING30-DAY RETURNSEXPERT SUPPORT
Aluminum Construction
5th Wheel available
Toolbox Compatible
Fuel Shotz Ready
80 Gal
Fuel Capacity
48.5" x 28" x 26"
Tank Dimensions
<1 Hour
Fuel Shotz Install
Spec'd Right for Your Truck Before It Ships

Spec'd Right for Your Truck Before It Ships

The worst call you can make is telling your crew the new auxiliary tank doesn't fit under their toolbox or blocks the 5th wheel hitch. That's wasted money and a week of downtime. Tank Vault runs a free pre-offer spec review on every order — we cross-reference your truck bed, toolbox configuration, and hitch setup against the ATI 80-gallon L-shape dimensions including the 2.5-inch fill neck height and 1.5-inch mounting tab extensions. If the fit doesn't work for your application, we catch it before the tank ships. No guessing, no return freight claims, no crew standing around waiting.

Extended Range Without Losing Bed Space

Extended Range Without Losing Bed Space

The L-shaped profile is purpose-built for trucks that run a crossover-style or chest toolbox. The bottom section of the tank nests under most standard toolboxes, giving you 80 gallons of additional diesel capacity without sacrificing storage. At 48.5 inches long by 28 inches wide by 26 inches high, this tank maximizes fuel volume in the space your toolbox already occupies. The geometry also maintains available for most 5th wheel hitch installations, so you don't have to choose between towing capability and fuel range. Aluminum construction keeps weight manageable while providing field-proven corrosion resistance for long-term diesel exposure.

Factory Filler Connection Keeps Install Under an Hour

Factory Filler Connection Keeps Install Under an Hour

The ATI Fuel Shotz diesel install kit — available as an add-on — connects the auxiliary tank directly to your factory fuel tank through the factory filler neck. No in-tank pumps, no return line modifications, no splicing into your OEM fuel system. The system keeps your factory tank full until the auxiliary tank is empty, so you monitor fuel level on your existing factory gauge. When the gauge drops from full, your 80-gallon reserve is depleted. This approach means a straightforward installation in under an hour and zero interference with your vehicle's factory fuel delivery components.

Compatibility Check

Verify these conditions before ordering to ensure proper fitment in your truck bed.

  • Bed height available of at least 26 inches for main tank body
  • Standard crossover-style or chest toolbox installed in bed
  • 5th wheel hitch configuration with adequate rear bed space

Built for the Road

This auxiliary tank is engineered for diesel trucks that work long distances and need to minimize fuel stops.

Long-Haul Fleet Routes
5th Wheel Towing
Remote Job Site Operations

Full specifications

At a glance

Dimensions
28 inches
Compliance
See product page
Warranty
See product page
Full specifications11 data points across 4 categories

Dimensions

Capacity80 Gallon
Length48.5 inches
Width28 inches
Height26 inches
Fill Neck Height Addition2.5 inches
Mounting Tab Extension1.5 inches to side and front

Power & Performance

Fuel TypeDiesel
Connection MethodFactory filler neck via ATI Fuel Shotz system

Materials

ConstructionAluminum

Compliance & Warranty

Compliance DocumentationSee product page
WarrantySee product page

The Tank Vault Promise

Pay as low as $72/month with Affirm. Every order ships free with full documentation support.

FREE Compliance DocumentationUL listing sheets, NFPA compliance certs, and EPA SPCC documentation included with every order — no chasing the manufacturer.
FREE Freight DeliveryLTL delivery to your site — call for liftgate, job-site delivery, or inside delivery options.
FREE Pre-offer Spec ReviewWe verify your application, jurisdiction, and compliance requirements before you order.
★★★★★
“Installed this on our F-350 with a Weather Guard crossover box. Tank fits tight underneath, no interference with the 5th wheel rail kit. Fuel Shotz hookup was straightforward — had it done in about 45 minutes. We run long hauls between fuel stops and this tank paid for itself in route efficiency inside two months. Tank Vault confirmed the dimensions against our bed before I ordered, which saved me from what could've been an expensive return.”
M
Marcus L.Odessa, TX

 

ATI aluminum diesel L-shaped auxiliary fuel tanks are designed to work with a crossover style toolbox or chest box. The bottom of the L-shape fits under most standard toolboxes. The L-shape also allows for clearance in most 5th wheel applications.

ATI diesel auxiliary tanks are used to increase driving range and fuel capacity by connecting directly into your factory fuel tank through the factory filler neck using the ATI Fuel Shotz system. 

ATI L-Shaped Auxiliary Tank Size:

  • 80 gallon – 48.5 inches long by 28 inches wide by 26 inches high 

*The fill neck adds 2.5 inches of height to the top of the tank and the mounting tabs add 1.5 inches to the side and front of the tank.

  • See all ATI Auxiliary Tank options to compare all ATI tank sizes available.

ATI FUEL SHOTZ (available as product add-on)

These tanks are designed for use with the ATI Fuel Shotz diesel install kits. The diesel FUEL SHOTZ installation kit can be installed in less than an hour.  The unique system connects the auxiliary tank to the factory tank vis the factory filler. 

This will keep your factory tank completely full until the auxiliary tank is empty. You will know your auxiliary tank is empty when your factory fuel gauge moves off the full mark. 

The FUEL SHOTZ system installs quickly and easily. No wires or switches to install.  The system has rollover protection on the tank and on the factory fill neck adaptor.  Detailed instructions are supplied with the FUEL SHOTZ installation kit. 

All ATI auxiliary tanks come standard with a 3/8″npt outlet, vent with rollover protection, automotive style fuel cap, and fully welded baffles to reduce slosh and add strength. 

These tanks are constructed from rugged diamond plate aluminum and are all available with a black or white powder coated finish. Custom tanks are available upon request. 

All ATI diesel auxiliary tanks come standard with the following:

  • Meets DOT requirements for diesel auxiliary.
  • All aluminum fuel tank construction.
  • Quick easy installation.
  • Tanks are baffled to reduce movement of contents.
  • No wires or switches to install.
  • Rollover protection.
  • Automotive style fill cap.
  • Hold down brackets.
  • Pressure and leak detection test.
  • Clean and free of debris inside and outside of the tank.
  • 1 year limited warranty.

Additional information

Size

80 Gallon

Reviews

There are no reviews yet.

Be the first to review “ATI 80-Gallon L-Shaped Auxiliary Diesel Fuel Tank”

Your email address will not be published. Required fields are marked *

Frequently Asked Questions

The ATI 80-gallon L-shaped tank is designed specifically for crossover-style and chest toolboxes. The bottom of the L nests under most standard toolbox designs. However, exact fitment depends on your specific toolbox dimensions, truck bed width, and mounting position. Contact Tank Vault before ordering with your toolbox make and model — we run a free pre-offer spec review to verify available including the 1.5-inch mounting tab extensions and 2.5-inch fill neck height.
Yes. The L-shaped profile is engineered to provide available for most 5th wheel hitch installations. The tank's geometry routes around the hitch area rather than occupying the center rear bed space where 5th wheel hitches mount. If you have an aftermarket or non-standard 5th wheel setup, send us the specifics before ordering and we'll confirm fitment against the 48.5 by 28 by 26-inch tank dimensions.
Yes. The ATI L-shaped auxiliary tank requires the Fuel Shotz diesel install kit — sold separately as an add-on — to function. This kit connects the auxiliary tank to your factory tank through the factory filler neck without modifying your OEM fuel system. The tank alone does not include the plumbing, hardware, or connection components needed to transfer fuel. Add the Fuel Shotz kit to your order to complete the installation.
Lead times vary based on current inventory at ATI and your delivery location. Auxiliary tanks ship via LTL freight. If you have a specific deadline — seasonal work, a job site mobilization, or a fleet schedule — contact us before ordering with your required delivery date. We'll confirm availability and coordinate freight to your site. Ships free to any address in the continental United States.
Tank Vault offers a 30-day return window on uninstalled tanks in original packaging. If the tank arrives and the fitment doesn't work for your application, contact us immediately. This is exactly why we offer the free pre-offer spec review — to catch fitment issues before the tank ships and avoid return freight altogether. Measure your bed, toolbox, and hitch available before ordering, or let us verify it for you.
This is an auxiliary diesel fuel tank designed for on-road use in pickup truck beds, manufactured by ATI, an established producer of auxiliary fuel tanks. Specific regulatory requirements vary by state and application. If your operation requires particular certifications or documentation for your jurisdiction, contact us before purchasing and we'll help you determine whether this tank meets your regulatory needs.
The 80-gallon rating refers to the tank body capacity at 48.5 inches long by 28 inches wide by 26 inches high. The fill neck adds 2.5 inches of height above the tank body and the mounting tabs add 1.5 inches to the side and front — these are dimensional extensions for installation available, not additional fuel capacity. Actual usable volume should be confirmed with ATI's specification sheets.
SKU: AUX80L Categories: , Brand:

The Tank Vault Promise

Pay as low as $72/month with Affirm. Every order ships free with full documentation support.

FREE Compliance Documentation UL listing sheets, NFPA compliance certs, and EPA SPCC documentation included with every order — no chasing the manufacturer.
FREE Freight Delivery LTL delivery to your site — call for liftgate, job-site delivery, or inside delivery options.
FREE Pre-offer Spec Review We verify your application, jurisdiction, and compliance requirements before you order.

Related products

About aluminum tank industries Fuel Transfer Tanks

aluminum tank industries is a trusted manufacturer of premium fuel transfer tanks. TankVault is an authorized dealer offering the full aluminum tank industries lineup with free delivery, price match guarantee, and expert support.

View all aluminum tank industries products →

Related Categories

Adapt Crossover Toolbox 1 products Aluminum Top Mount Drop Down Box 1 products Aluminum Top Mount Swing Up Box Series P 1 products Aluminum Underbody Barn Door Box 1 products Aluminum Underbody Box Flush Mount 1 products Aluminum Underbody Box Series M 1 products
Join the Grill Island Community

Expert Picks, Straight to Your Inbox

No spam. Just the gear worth knowing about.

No spam. Unsubscribe anytime.