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Tread Plate Finish
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RDS Rectangular Aluminum Auxiliary Diesel Fuel Tanks

Smooth Mill or Diamond Plate - 20, 33, 40 or 60 Gallon

Tread Plate Finish
$576.95 - $849.95
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  • A DOT-approved Auxiliary tank that can be used to integrate into your diesel truck's fuel system.
  • No-Rust 0.125" thick heavy-duty aluminum construction.
  • Mounted Fuel level sight gauge.
  • Aluminum keeps fuel from being contaminated from internal corrosion.

RDS Aluminum Auxiliary Fuel Tanks let you carry on with fewer stops to gas up. Shop DOT-compliant RDS auxiliary tanks for diesel vehicles that go the distance at Leonard Accessories.

Aluminum truck fuel tanks are the best choice because aluminum protects fuel from internal corrosion contamination. Choose 20- to 60-gallon capacity aluminum auxiliary fuel tanks, and add an installation kit for DIY ease.

Check out these superior features of RDS aluminum diesel tanks:

  • No-Rust 0.125-inch-thick heavy-duty aluminum construction
  • Mounted fuel level sight gauge
  • Fully welded seams that are 100% pressure tested for leaks
  • Internal built-in baffles to reduce sloshing and weight transfer
  • DOT Approved rollover safety valve (vent)
  • Included 3/8-inch FTP drain plug
  • Gas cap, suction tube, drain fittings, and fuel filler shroud included

Contact Leonard Accessories for guidance measuring your truck for an auxiliary fuel tank or to explore financing options.

Tank and Toolbox Measurements in Inches

Part Number Finish Gallons  A B C
         75287 Mill         20 18 20 14
         71804 Brite Diamond Tread         33   9 50 20
         72771 Brite Diamond Tread         60 12.75 55 20
         70387** Brite Diamond Tread         40 9 60 20.5
**Notched Bottom Down 1.75" Notched In 4"      

A Tank is Not Just a Tank - The tank and toolbox combo listed here is considered an auxiliary tank. In the fuel tank world, a "Transfer Tank" is one that's used with a pump attached to fuel equipment or vehicles other than the vehicle carrying the tank. However, there's no rule against refueling the truck carrying the tank. The main thing is that the tank is not part of the truck's own fuel system. Tanks that are integrated into the truck's factory fuel system are "Auxiliary Tanks". The tanks here are Auxiliary ONLY and cannot be equipped with a pump for transferring fuel. Gravity feed installation kits to complete the installation are available here.

It Pays To Buy The Best - On some things, quality and experience should be your first consideration. RDS has been building aluminum transfer and auxiliary tanks for over 45 years. RDS products build quality meets DOT's stringent standards. Thick 1/8" aluminum, continuously welded seams, and pressure testing for leaks are all part of the RDS manufacturing process. Each tank comes with gas cap, suction tube, drain fittings, manual sight gauge, fuel filler shroud, along with internal baffles to reduce sloshing. Toolboxes come with linked stainless steel locks that also secure the fuel fill to prevent tampering, and two lift cylinders to hold open the crowned lid.

Hook Up Easily - Gravity Feed auxiliary fuel tank installation kits are sold separately (Item #s 011025, 011029 and 011408 sold separately Not intended to be used for gasoline.) They are a simple and economical way to integrate your auxiliary tank into your diesel pickup truck's fuel system. These kits contain everything you need to make the connection from the auxiliary tank with a 3/8" NPT bottom fitting to the factory fill tube. The auxiliary tank keeps the factory tank full. When the auxiliary tank is empty your factory fuel gauge will move off the full mark. These kits are supplied with detailed instructions and take less than an hour to install. There are no wires or switches to install, engineered for rollover protection, and only requires attaching the kit supplied 3/8" npt pipe fitting on the bottom of the tank in place of the drain fitting and splicing the filler neck adapter into your truck's fuel tank filler tube.

Big Brother is Watching - RDS Auxiliary Tanks are built to DOT standards. Laws governing the use of auxiliary tanks will vary from State to State - so we STRONGLY suggest that local and state-level ordinances be reviewed before the purchase of any transfer or auxiliary tank.

You Do Have Some Work To Do - RDS offers many different configurations, capacities, and shapes but measuring the area you intend to mount your tank is the only way to correctly choose the right tank for your truck. Use our guide "How to Measure Your Truck Bed for a Transfer or Auxiliary Tank"

What You Need To Know:

Real truck lovers, off-roaders, or fans of anything auto, be a truck hero and buy the best quality, best-reviewed, best priced RDS Aluminum products through Leonard Truck Accessories .

Since opening in 1963 Leonard Buildings and Truck Accessories' goal has always been to provide quality truck accessories at the lowest prices. Ford, Chevy, GMC, Dodge, Ram, Nissan, Honda, Jeep, and Toyota Truck owners may disagree on which vehicle brand is better but they can all agree that Leonard Truck Accessories is the perfect place to buy your RDS Rectangular AUX Tank.

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