Best Auxiliary Diesel Fuel Tank for Truck Use

#1 · Best Overall

1. Dee Zee DZ91752X

• Capacity: 39 gallons
• Material: Aluminum
• Weight: 12 lb

Best for: Narrow-bed diesel transfer.

Why it ranks #1: Its 39-gallon aluminum tank is described as meeting federal DOT requirements and connecting to an OEM fuel line; it also supports center-mounted transfer pumps.

A narrow profile is the defining detail of the Dee Zee DZ91752X, a 39-gallon aluminum auxiliary tank that can suit buyers working around constrained truck-bed space. It is certified to meet federal DOT requirements, and its stated compatibility with center-mounted transfer pumps helps identify a specific installation approach.

The 39-gallon capacity offers a defined reserve without moving into the larger capacities listed elsewhere, while the narrow designation makes bed-space planning central to this choice. Dee Zee specifies compatibility with center-mounted transfer pumps and connection to an OEM fuel line, linking the tank to a particular transfer workflow. Its non-rusting Brite-Tread aluminum, vented cap, full-weld stability baffles, and drain plug add relevant material and handling details; the tank is hydrostatically tested to 29 psi.

Skip it if you need more than 39 gallons of capacity; the RDS MFG INC 70326 lists 69 gallons for higher-volume storage.

Pick the Dee Zee when a narrow 39-gallon footprint, federal DOT compliance, and stated center-pump compatibility match the truck and transfer plan. Its connection to an OEM fuel line is relevant, so confirm that workflow suits the intended setup.

Listed on Amazon as: Dee Zee DZ91752X (39 gallon) Narrow Auxiliary Diesel Fuel Transfer Tank

#2 · Highest Capacity

2. RDS 70326 Rectangular Tank

• Capacity: 69 gallons
• Material: Aluminum
• Weight: 16 oz

Best for: High-capacity auxiliary storage.

Why it ranks #2: The 69-gallon aluminum tank offers the largest stated capacity here, and RDS describes diesel gravity feed from the tank bottom.

The 69-gallon capacity gives this RDS rectangular aluminum tank room for extended diesel storage, while its 57-by-18-by-16-inch dimensions provide concrete measurements for planning a truck-bed installation. RDS describes diesel gravity feed from the tank bottom, connecting stored fuel with an auxiliary supply workflow when the appropriate installation is in place.

With 69 gallons of capacity, this is the largest listed RDS tank in this roundup, a useful distinction for buyers prioritizing stored diesel volume. Its 57-by-18-by-16-inch rectangular footprint helps assess available bed space before installation, and aluminum construction keeps the material choice clear. RDS says diesel can gravity-feed from the bottom when connected to the vehicle tank; the optional Diesel Install Kit is a separate consideration. Gasoline use is limited to top siphoning with an electric fuel pump.

Skip it if you need a narrow, documented 39-gallon certified tank; the Dee Zee DZ91752X lists DOT compliance and center-pump compatibility.

Choose this RDS for truck owners seeking 69 gallons of auxiliary diesel storage and a stated gravity-feed path. Check the 57-inch length and 18-inch width against available bed space, and account separately for the optional installation kit.

Listed on Amazon as: RDS MFG INC Rectangular Auxiliary Fuel Tank – 69 Gallon

#3 · Toolbox Combo

3. Dee Zee DZ92740XB

• Weight: 50 lb

Best for: Tank-and-toolbox haulers.

Why it ranks #3: This 43-gallon aluminum combo pairs a transfer tank with a utility chest and lists three stability baffles, a lockable cap, and a venting coupler.

The Dee Zee DZ92740XB combines a 43-gallon transfer tank with a utility chest, giving truck owners fuel storage and toolbox space in one connected assembly. Its black powder-coat finish over Brite-Tread aluminum adds a protective surface, while the listed 54-by-18-by-16-inch overall dimensions help evaluate bed layout.

The connected utility chest and transfer tank consolidate two truck-bed functions, which can free the buyer from planning separate storage units. The 43-gallon capacity provides a defined fuel reserve, and .125-inch Brite-Tread aluminum with a black powder-coat finish specifies both construction and surface treatment. Dee Zee also lists three stability baffles, a lockable cap, venting coupler, and .375-inch drain plug, giving buyers concrete details to consider for containment, access, and draining workflow.

Skip it if you need the roundup's largest listed capacity; the RDS MFG INC 70326 holds 69 gallons rather than 43.

This Dee Zee suits truck owners who want a combined toolbox and diesel transfer tank, with baffles, a lockable cap, and drain plug specified. Its 43-gallon capacity and listed dimensions should fit the buyer's storage and bed-space priorities.

Listed on Amazon as: Dee Zee DZ92740XB (43 gallon) Auxiliary Diesel Fuel Transfer Tank – Black Aluminum

#4

4. RDS 72548 Combo Tank

• Capacity: 60 gallons
• Material: Alloy Steel, Aluminum, Stainless Steel
• Weight: 16 oz

Best for: Toolbox-combo diesel storage.

Why it ranks #4: The 60-gallon RDS toolbox-combo format adds storage alongside an auxiliary tank, and the product description says diesel can gravity-feed.

The RDS 72548 pairs a 60-gallon auxiliary fuel tank with a toolbox, enabling truck owners to combine fuel storage and equipment space in one product. Its listed 55-by-20-by-19.5-inch dimensions make bed-layout planning concrete, while RDS describes diesel gravity feed from the tank bottom.

A 60-gallon capacity provides substantial auxiliary storage, and the toolbox-combo format puts fuel and tools into a single truck-bed footprint rather than treating them as separate purchases. The listed 55-by-20-by-19.5-inch dimensions help buyers assess that footprint before installation. RDS says its auxiliary tanks connect to the vehicle fuel tank and that diesel can gravity-feed from the bottom; an optional Diesel Install Kit is referenced, so plan the fuel connection separately from the tank-and-toolbox purchase.

Skip it if you want a documented pump, hose, and nozzle included; the BLACKHORSE-RACING LZ69801 lists those transfer components.

This RDS combination fits truck owners who need 60 gallons of auxiliary diesel storage alongside toolbox space. Measure for its 55-by-20-inch footprint and account for the optional installation kit before relying on the stated gravity-feed connection.

Listed on Amazon as: RDS MFG INC – 72548 Fuel Transfer Tank/Auxiliary Fuel Tank/Toolbox Combo – 60 Gallon

#5 · Short-Bed Fit

5. RDS 71212 Fuel Tank

• Capacity: 60 gallons
• Material: Aluminum
• Weight: 61 lb

Best for: Short-bed auxiliary fueling.

Why it ranks #5: This 60-gallon aluminum tank is listed at 56 by 13 by 19.25 inches and fits some short beds, though buyers should measure first.

The 60-gallon RDS tank is listed as fitting some short beds, giving truck owners a substantial auxiliary supply in a bed-specific format. Its 56-by-13-by-19.25-inch dimensions make space planning measurable, and RDS describes diesel gravity feed from the tank bottom when connected to the vehicle tank.

At 60 gallons, this aluminum tank offers a sizable auxiliary reserve, while its 13-inch width and 56-inch length give buyers useful measurements for assessing a short-bed layout. RDS says diesel can gravity-feed from the bottom after connection to the vehicle fuel tank, supporting an auxiliary-fueling workflow. The fit note is limited to some short beds, so dimensions still matter. For gasoline, the listing permits top siphoning with an electric pump and explicitly disallows transfer to another vehicle.

Skip it if you need a stated DOT-certified tank; the Dee Zee DZ91752X lists federal DOT compliance.

This RDS fits truck owners seeking 60 gallons of auxiliary diesel storage and considering a short-bed installation. Measure the listed 56-by-13-inch footprint carefully; the short-bed fit applies only to some beds, and gasoline transfer is restricted.

Listed on Amazon as: RDS MFG INC Fuel Tank – 60-Gallon

#6

6. RDS 71083 Rectangular Tank

• Capacity: 45 gallons
• Material: Aluminum
• Weight: 42 lb

Best for: Welded aluminum transfer tank.

Why it ranks #6: Its 45-gallon aluminum tank has fully welded seams, and the RDS description identifies diesel gravity feed as an available auxiliary-fueling setup.

Fully welded seams distinguish this 45-gallon RDS aluminum transfer tank, with the construction detail supporting a durability-focused buying decision. The aluminum material is also specified as non-rusting, while RDS describes diesel gravity feed from the tank bottom for an auxiliary supply connected to a vehicle tank.

The 45-gallon capacity gives this rectangular tank a middle-ground storage option among the listed RDS models. Its fully welded seams and aluminum construction, which the listing identifies as non-rusting, offer buyers specific construction details to weigh for ongoing storage and transport. RDS describes auxiliary connection to a vehicle fuel tank and diesel gravity feed from the bottom, linking the tank to a practical fueling setup. Gasoline auxiliary fueling is permitted only by top siphon using an electric fuel pump.

Skip it if you need listed dimensions for bed-space planning; the RDS MFG INC 71212 specifies a 56-by-13-inch footprint.

Choose this RDS for 45 gallons of aluminum auxiliary storage with fully welded seams and a stated diesel gravity-feed path. Because dimensions are not provided here, buyers needing precise bed-layout planning should prioritize a tank with listed measurements.

Listed on Amazon as: RDS MFG INC 71083 Rectangular Auxiliary/Transfer Fuel Tank – 45 Gallon Capacity

#7 · Low-Profile Format

7. RDS 71804 Auxiliary Tank

• Capacity: 37 gallons
• Material: Aluminum
• Weight: 77 lb

Best for: Low-profile auxiliary tank.

Why it ranks #7: The 37-gallon aluminum tank measures 50 by 20 by 9 inches, a shallow listed profile that may suit buyers checking bed clearance.

At nine inches high, the RDS 71804 gives buyers a low-profile 37-gallon aluminum tank to consider where vertical bed space matters. Its listed 50-by-20-by-9-inch dimensions make the footprint explicit, and RDS describes diesel gravity feed from the bottom when connected to a vehicle fuel tank.

The 37-gallon capacity provides auxiliary storage in a comparatively low nine-inch listed height, making vertical clearance a central fit consideration. Its 50-by-20-inch base dimensions let buyers assess the floor-space tradeoff before installation. RDS describes connection to the vehicle fuel tank and diesel gravity feed from the bottom, outlining an auxiliary supply workflow. Gasoline use is limited to top siphoning with an electric fuel pump, so that stated method matters when evaluating fuel compatibility.

Skip it if you need a larger reserve; the RDS MFG INC 70326 lists 69 gallons and the 71212 lists 60.

This RDS suits buyers prioritizing a low-profile aluminum tank with 37 gallons of auxiliary capacity. Check its 50-by-20-inch footprint against available bed space, and account for the specified top-siphon-only method when using gasoline.

Listed on Amazon as: RDS MFG INC Auxiliary Fuel Tank 37Gal – 71804

#8

8. BLACKHORSE-RACING 51-Gallon Combo

• Capacity: 51 gallons
• Material: Aluminum

Best for: Powered transfer and toolbox.

Why it ranks #8: This 51-gallon aluminum toolbox combo includes a 10 GPM, 12V DC pump, automatic nozzle, and 13.1-foot hose; the listing does not specify certification.

A listed 10-GPM, 12-volt pump with automatic nozzle and 13.1-foot hose makes this 51-gallon BLACKHORSE-RACING combo ready for a powered transfer workflow. The black aluminum tank also incorporates a toolbox, letting buyers combine fuel storage and equipment space in one assembly.

The 10-GPM 12-volt pump, automatic refueling nozzle, and 13.1-foot hose connect the 51-gallon tank to a powered refueling workflow without leaving those transfer components unspecified. The black aluminum construction is described as rust- and corrosion-resistant, while the combo format adds toolbox utility. A double lock and keys protect the internal pump and supplies. The listing explicitly says the package does not contain a filter, a relevant equipment detail for buyers planning their transfer setup.

Skip it if you require a filter in the package; the listing excludes one, while the Dee Zee DZ91752X focuses on a pump-compatible tank.

Choose this BLACKHORSE-RACING combo if powered transfer, a 51-gallon reserve, and toolbox storage match your truck workflow. The pump, nozzle, and hose are listed, but the absent filter means buyers must account for that limitation.

Listed on Amazon as: 51 Gallons Combo Aluminum Fuel Transfer Tank, with 10 GPM Fuel Transfer Pump/Gasoline Diesel Transfer Tank & Toolbox/Auxiliary Fuel Tank-Black

#9

9. Landrol 58-Gallon Tank

• Capacity: 58 gallons
• Material: Aluminum

Best for: Gauge-ready removable storage.

Why it ranks #9: Its 58-gallon aluminum tank includes a sending unit and fuel-gauge connection, but the listing explicitly says it has not been DOT certified.

A sending unit that connects to a fuel gauge gives this 58-gallon Landrol tank a direct way to check remaining capacity. Its 59-by-13-by-17-inch aluminum body is notably narrow, and the listing specifies fully welded mounting brackets plus two straps for truck installation and removal.

The sending unit connects to a fuel gauge, making remaining capacity easier to check without relying only on the tank's nominal 58-gallon size. At 59 by 13 by 17 inches, its narrow listed width helps buyers evaluate bed-space use. Fully welded mounting brackets support truck installation, while two straps are provided to make removal from the vehicle more convenient. The important limitation is explicit: this tank has not been certified by DOT, a consideration for transport requirements.

Skip it if you require stated DOT certification; the Dee Zee DZ91752X says it meets federal DOT requirements.

This Landrol suits truck owners who value a gauge-connected sending unit and a removable 58-gallon aluminum tank. Its narrow dimensions and straps aid planning, but buyers must weigh the explicit lack of DOT certification for their use.

Listed on Amazon as: 58 Gallon Aluminum Fuel Cell Tank Rectangular Transfer Fuel Tank Auxiliary Diesel Storage for Transportation Truck

#10

10. Better Built 29211584

• Capacity: 36 gallons
• Material: Alloy Steel
• Weight: 40 lb

Best for: Spill-conscious steel transfer.

Why it ranks #10: This 36-gallon steel transfer tank includes a lockable cap and mounting kit, but its listing does not describe an auxiliary connection to the vehicle fuel line.

An overfill restriction that automatically shuts off the pump is the key feature of this 36-gallon Better Built steel tank, helping address spills during refueling. Built-in baffles limit shifting in transit, while its flush-mounted two-inch inlet and outlet bungs are specified for fast flow.

The automatic pump shutoff from the overfill restriction gives this tank a distinct refueling safeguard, while built-in baffles add strength and help keep contents from shifting during transport. Two-inch flush-mounted inlet and outlet bungs support a fast-flow setup, and the 36-gallon capacity defines the available reserve. Alloy-steel construction and the included vented lockable cap and mounting kit with rubber bushings are practical installation and access details for truck owners planning a transfer-tank arrangement.

Skip it if you need a 50-gallon-plus reserve; the Dee Zee DZ92740XB lists 43 gallons and the RDS MFG INC 70326 lists 69.

The Better Built suits buyers who prioritize its overfill shutoff, baffles, and fast-flow bungs in a 36-gallon steel tank. Its capacity is the boundary to weigh, along with planning installation around the included mounting kit.

Listed on Amazon as: Better Built Steel Transfer Fuel Tank – 36-Gallon, Rectangular, Black, Model Number 29211584