A strong universal spare-tire fuel tank choice needs a form and mounting arrangement that suit your vehicle, plus a clearly stated capacity and fuel compatibility. The six products here include compact, bracket-equipped round aluminum tanks and larger truck-bed tank-and-toolbox combinations, so they are not interchangeable. None of the listings specifically confirms spare-tire mounting or provides a spare-tire fitment chart; treat that as a point to verify before buying.
For a compact round tank, the JSD AUTO PARTS M223 is a practical starting point: it holds 5.5 gallons and includes two brackets, a cap, and a housing. If you need substantially more capacity, compare the RDS options, but note that their descriptions say they are not for gasoline.
The JSD AUTO PARTS M223 is the best overall match among these listings for shoppers seeking a compact, round auxiliary tank that might suit a spare-tire-style installation. It holds 5.5 gallons, is aluminum, and comes with two mounting brackets, a cap, and a housing. However, the product data does not confirm spare-tire mounting or compatibility with a particular vehicle, so verify the mounting dimensions and intended fuel before purchasing.
Our Top Picks
Best OverallIts compact 5.5-gallon round aluminum format and included two brackets, cap, and housing make it the closest listed option to a compact auxiliary setup.
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Mid-Size CapacityThis round 8-gallon tank includes two mounting brackets and is listed for cars and trucks, though spare-tire mounting is not confirmed.
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Largest Round TankIts 15.88-gallon aluminum round tank offers the greatest capacity among the bracket-equipped JSD options and includes a cap and housing.
View on Amazon- Compact Toolbox Tank RDS MFG INC 72773
Compare Tank Types, Capacities, and Fit Considerations
| # | Product | Capacity | Material | Weight | Compatible with Vehicle Type | Buy |
|---|---|---|---|---|---|---|
| 1 | 1. JSD AUTO PARTS M223Best Overall | 5.5 gallons | Aluminum | 8.9 lb | Car | View on Amazon |
| 2 | 2. JSD AUTO PARTS M271Mid-Size Capacity | 8 gallons | Alloy Steel, Aluminum | 10.4 lb | Car, Truck | View on Amazon |
| 3 | 3. JSD AUTO PARTS M311Largest Round Tank | 15.88 gallons | Aluminum | 15.8 lb | Car | View on Amazon |
| 4 |  4. RDS MFG INC 72773Compact Toolbox Tank | 41 gallons | Aluminum | 120 lb | Truck | View on Amazon |
| 5 |  5. RDS MFG INC 72746High-capacity truck toolbox combo | 90 gallons | Aluminum | 87 lb | Truck | View on Amazon |
| 6 |  6. RDS MFG INC 72772Deep-bed 90-gallon truck setup | 90 gallons | Aluminum | 115 lb | Truck | View on Amazon |
Detailed Reviews: Best Universal Spare Tire Fuel Tank
#1 · Best Overall
1. JSD AUTO PARTS M223
- Capacity: 5.5 gallons
- Material: Aluminum
- Weight: 8.9 lb
- Compatible with Vehicle Type: Car
Best for: Compact 5.5-gallon auxiliary tank.
Why it ranks #1: Its compact 5.5-gallon round aluminum format and included two brackets, cap, and housing make it the closest listed option to a compact auxiliary setup.
A 5.5-gallon capacity in an 8-by-26-inch spun aluminum round tank gives buyers a compact auxiliary-fuel format rather than a large truck-bed toolbox combo. Its 1/4-inch NPT outlet and two powder-coated steel mounting brackets identify the connection and mounting details to plan around.
The round 8-by-26-inch form and 5.5-gallon capacity suit buyers seeking a smaller auxiliary tank than a 90-gallon truck-bed unit. Two powder-coated black steel brackets are included for mounting, with the coating described as rust-free; that included hardware helps establish the installation approach. The title specifies an end fill and a 1/4-inch NPT outlet, useful details for planning access and plumbing. It is listed as compatible with cars, and weighs 8.9 pounds.
- 5.5-gallon capacity in an 8-by-26-inch round tank
- Aluminum construction
- Two powder-coated black steel mounting brackets included
- End fill and 1/4-inch NPT outlet
- Its 5.5-gallon capacity is limited for buyers seeking a large reserve.
Skip it if you need more than 5.5 gallons of auxiliary capacity; the JSD 15.875-gallon M311 offers a larger listed reserve.
Car owners looking for a small round auxiliary tank with included mounting brackets can consider this 5.5-gallon JSD. Its end-fill layout and 1/4-inch NPT outlet are key fit considerations for installation planning.
Full product details
| Brand | JSD AUTO PARTS |
|---|---|
| Capacity | 5.5 gallons |
| Compatible with Vehicle Type | Car |
| Included Components | Comes with 2 brackets, Comes with cap, Comes with housing |
| Item Weight | 8.9 pounds |
| Manufacturer | JSD AUTO PARTS |
| Part Number | M223 |
| Manufacturer Warranty Description | Three years quality warranty |
| Material | Aluminum |
| Model Number | Fuel tank |
Listed on Amazon as: JSD 5.5 Gallons 8"x26" Universal Auxiliary Aluminum Spun Round Gas Tank End Fill 1/4" NPT Outlet
View on Amazon#2 · Mid-Size Capacity
2. JSD AUTO PARTS M271
- Capacity: 8 gallons
- Material: Alloy Steel, Aluminum
- Weight: 10.4 lb
- Compatible with Vehicle Type: Car, Truck
Best for: Center-fill 8-gallon tank.
Why it ranks #2: This round 8-gallon tank includes two mounting brackets and is listed for cars and trucks, though spare-tire mounting is not confirmed.
A center-fill opening paired with an 8-gallon spun round tank gives buyers a defined fill location in a compact auxiliary-fuel format. The 10-by-24-inch dimensions and 3/8-inch NPT outlet help determine whether its shape and connection suit the intended installation.
The 8-gallon capacity and 10-by-24-inch round profile provide a smaller alternative to a large toolbox-style tank, while the center-fill arrangement identifies where filling access is located. Its 3/8-inch NPT outlet is a specific plumbing detail to match against the planned setup. Two powder-coated black steel brackets are included for mounting, and the listing names both cars and trucks as compatible vehicle types. The listed materials are alloy steel and aluminum; weight is 10.4 pounds.
- 8-gallon capacity in a 10-by-24-inch round tank
- Center-fill layout
- 3/8-inch NPT outlet
- Two powder-coated black steel mounting brackets included
- Its 8-gallon capacity is modest for buyers needing a larger auxiliary reserve.
Skip it if you need more than 8 gallons in one tank; the JSD 15.875-gallon M311 provides greater listed capacity.
Car or truck owners seeking an 8-gallon round tank with center fill may find this JSD suitable when its 10-by-24-inch dimensions fit. Check the planned connection against the 3/8-inch NPT outlet.
Full product details
| Brand | JSD AUTO PARTS |
|---|---|
| Capacity | 8 gallons |
| Compatible with Vehicle Type | Car, Truck |
| Item Weight | 10.4 pounds |
| Manufacturer | JSD AUTO PARTS |
| Part Number | M271 |
| Material | Alloy Steel, Aluminum |
Listed on Amazon as: JSD 8 Gallons 10"x24" Aluminum Auxiliary Spun Round Gas Tank Fuel Cell Tank Center Fill 3/8" NPT Outlet
View on Amazon#3 · Largest Round Tank
3. JSD AUTO PARTS M311
- Capacity: 15.88 gallons
- Material: Aluminum
- Weight: 15.8 lb
- Compatible with Vehicle Type: Car
Best for: Higher-capacity round auxiliary tank.
Why it ranks #3: Its 15.88-gallon aluminum round tank offers the greatest capacity among the bracket-equipped JSD options and includes a cap and housing.
A listed 15.88-gallon capacity in a 12-by-33-inch spun round aluminum tank offers more reserve than the smaller JSD round options. The center-fill design and 3/8-inch NPT outlet specify the fill access and connection, while two included brackets support mounting planning.
The 12-by-33-inch dimensions and 15.8-pound listed weight help buyers evaluate space and handling for installation. Its 15.88-gallon capacity provides more auxiliary fuel than compact 5.5- and 8-gallon options, while the center-fill arrangement establishes where to access the tank. A 3/8-inch NPT outlet gives a defined connection specification to match to the intended setup. Two powder-coated black steel brackets are included, and the listing identifies car compatibility.
- 15.88-gallon listed capacity
- 12-by-33-inch spun round aluminum tank
- Center-fill design with 3/8-inch NPT outlet
- Two powder-coated black steel brackets included
- Its 33-inch length requires more installation space than the 8-by-26-inch JSD M223.
Skip it if you have room only for a shorter tank; the JSD M223 measures 8 by 26 inches and has included mounting brackets.
Car owners seeking a larger round auxiliary tank with center fill can consider this JSD if a 12-by-33-inch footprint fits their installation. The 3/8-inch NPT outlet and included brackets are relevant setup considerations.
Full product details
| Brand | JSD AUTO PARTS |
|---|---|
| Capacity | 15.88 gallons |
| Compatible with Vehicle Type | Car |
| Included Components | Comes with 2 brackets, Comes with cap, Comes with housing |
| Item Weight | 15.8 pounds |
| Manufacturer | JSD AUTO PARTS |
| Part Number | M311 |
| Manufacturer Warranty Description | Three years quality warranty |
| Material | Aluminum |
| Model Number | Fuel tank |
Listed on Amazon as: JSD 15.875 Gallons 12"x33" Aluminum Spun Round Gas Tank with Brackets Center Fill 3/8" NPT Outlet
View on Amazon#4 · Compact Toolbox Tank
4. RDS MFG INC 72773
- Capacity: 41 gallons
- Material: Aluminum
- Weight: 120 lb
- Compatible with Vehicle Type: Truck
Best for: Lower-capacity truck toolbox combo.
Why it ranks #4: The 41-gallon aluminum tank-and-toolbox combination is smaller than the other RDS options and lists universal fit, but is a truck-oriented format.
A 41-gallon auxiliary tank and built-in toolbox combine fuel storage with a reinforced-lid storage compartment in a 55-by-18-by-21.75-inch truck unit. Its narrower listed width than a 24-inch-deep toolbox combo can help buyers compare bed-space requirements before choosing an integrated setup.
The 41-gallon capacity offers less auxiliary fuel than a 90-gallon combo, while the 55-by-18-by-21.75-inch dimensions give buyers concrete measurements for assessing truck-bed fit. At 120 pounds, it also requires planning for handling and installation. Aluminum diamond-tread construction is described as non-rusting, and fully welded seams plus a reinforced toolbox lid support the combined-use format. The manufacturer states it is not for gasoline; users are responsible for complying with safe transportation and loading requirements.
- 41-gallon auxiliary fuel capacity
- Built-in toolbox combines storage and tank
- Aluminum construction is described as non-rusting
- Fully welded seams and reinforced toolbox lid
- Not for use with gasoline.
Skip it if you need gasoline compatibility or a lighter unit; this RDS combo weighs 120 pounds and measures 55 inches long.
Truck owners who want an integrated toolbox and 41 gallons of auxiliary capacity can consider this narrower-width RDS combo if its dimensions suit the bed. It is not for gasoline, and the 120-pound weight merits installation planning.
Full product details
| Brand | RDS MFG INC |
|---|---|
| Capacity | 41 gallons |
| Compatible with Vehicle Type | Truck |
| Included Components | Fuel Tank,New |
| Item Dimensions | 55 x 18 x 21.75 inches |
| Item Weight | 120 pounds |
| Dimensions | 55 x 18 x 21.75 inches |
| Manufacturer | RDS MFG INC |
| Part Number | 72773 |
| Manufacturer Warranty Description | Manufacturer Warranty |
| Material | Aluminum |
| Model Number | 72773 |
| Additional Information | Important Information Proposition 65 Warning for California Consumers WARNING: This product can expose you to chemicals including styrene which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov Proposition 65 Warning for California Consumers WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov |
Listed on Amazon as: RDS MFG INC 72773 Fuel Tank
View on Amazon#5
5. RDS MFG INC 72746
- Capacity: 90 gallons
- Material: Aluminum
- Weight: 87 lb
- Compatible with Vehicle Type: Truck
Best for: High-capacity truck toolbox combo.
Why it ranks #5: This 90-gallon aluminum tank and toolbox lists universal fit for trucks, but its 52-inch length and gasoline restriction make it unlike a compact spare-tire tank.
A 90-gallon aluminum auxiliary tank paired with a built-in toolbox gives truck owners substantial extra fuel capacity while combining storage in one unit. Its diamond-tread construction, fully welded seams, and reinforced lid make the integrated tank-and-toolbox format the defining practical choice.
The 52-by-21-by-19-inch footprint and 87-pound weight are important to account for when planning truck-bed space and installation. Aluminum construction is described as non-rusting, while fully welded seams and a reinforced toolbox lid support a robust combined storage setup. With 90 gallons of capacity, it serves as an auxiliary tank rather than a compact reserve. The manufacturer specifies that it is not for gasoline, so intended fuel and applicable transport requirements matter before purchase.
- 90-gallon auxiliary fuel capacity
- Built-in toolbox combines fuel and tool storage
- Aluminum construction is described as non-rusting
- Fully welded seams and reinforced toolbox lid
- Not for use with gasoline.
Skip it if you need gasoline compatibility or a compact, lightweight tank; this unit weighs 87 pounds and measures 52 by 21 by 19 inches.
Truck owners seeking 90 gallons of auxiliary capacity with a built-in toolbox should consider this RDS combo when their bed can accommodate its 52-by-21-inch footprint. It is not suitable for gasoline, and safe transport requirements remain the user's responsibility.
Full product details
| Brand | RDS MFG INC |
|---|---|
| Capacity | 90 gallons |
| Compatible with Vehicle Type | Truck |
| Included Components | Fuel Tank,New |
| Item Dimensions | 52 x 21 x 19 inches |
| Item Weight | 87 pounds |
| Dimensions | 52 x 21 x 19 inches |
| Manufacturer | RDS MFG INC |
| Part Number | 72746 |
| Manufacturer Warranty Description | Manufacturer Warranty |
| Material | Aluminum |
| Model Number | 72746 |
| Additional Information | Important Information Proposition 65 Warning for California Consumers WARNING: This product can expose you to chemicals including styrene which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov |
Listed on Amazon as: RDS MFG INC 72746 Fuel Tank
View on Amazon#6
6. RDS MFG INC 72772
- Capacity: 90 gallons
- Material: Aluminum
- Weight: 115 lb
- Compatible with Vehicle Type: Truck
Best for: Deep-bed 90-gallon truck setup.
Why it ranks #6: It is a 90-gallon truck tank-and-toolbox with universal fit, but its 55-inch length and stated gasoline restriction make it the least suited to a spare-tire-style setup.
A 90-gallon capacity in a 55-by-24-by-22.25-inch aluminum tank-and-toolbox combo suits truck owners who can devote substantial bed space to auxiliary fuel and storage. The built-in toolbox, fully welded seams, and reinforced lid bring the key distinction: one unit serves both functions.
At 115 pounds, this unit calls for planning around its weight as well as its 55-by-24-by-22.25-inch dimensions; those measurements help determine whether the truck bed can accommodate it. Aluminum construction is described as non-rusting, and the fully welded seams and reinforced toolbox lid support its combined tank-and-storage role. The 90-gallon capacity is substantial, but the manufacturer explicitly says it is not for gasoline. Users are responsible for meeting safe transportation and loading requirements.
- 90-gallon auxiliary fuel capacity
- Built-in toolbox adds storage alongside the tank
- Aluminum construction is described as non-rusting
- Fully welded seams and reinforced toolbox lid
- Its 115-pound weight and 55-by-24-inch footprint require substantial bed space.
Skip it if you have limited truck-bed room or need a lighter unit; this combo weighs 115 pounds and measures 55 by 24 by 22.25 inches.
Truck owners wanting 90 gallons plus an integrated toolbox may find this RDS model appropriate if their bed has room for its larger footprint. It is not for gasoline, and the listed safe-loading responsibilities still apply.
Full product details
| Brand | RDS MFG INC |
|---|---|
| Capacity | 90 gallons |
| Compatible with Vehicle Type | Truck |
| Included Components | Fuel Tank,New |
| Item Dimensions | 55 x 24 x 22.25 inches |
| Item Weight | 115 pounds |
| Dimensions | 55 x 24 x 22.25 inches |
| Manufacturer | RDS MFG INC |
| Part Number | 72772 |
| Manufacturer Warranty Description | Manufacturer Warranty |
| Material | Aluminum |
| Model Number | 72772 |
| Additional Information | Important Information Proposition 65 Warning for California Consumers WARNING: This product can expose you to chemicals including styrene which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov |
Listed on Amazon as: RDS MFG INC 72772 Fuel Tank
View on AmazonCheck mounting before treating a round tank as spare-tire compatible
A round shape and included brackets do not establish that a tank mounts to a spare tire. The three JSD listings describe spun round tanks and include two brackets, but none specifies a spare-tire carrier, bolt pattern, strap arrangement, or vehicle fitment. Compare the tank’s actual dimensions with the available mounting area and ask the seller or installer to confirm how the brackets attach and whether they safely support a filled tank.
A mismatch can leave the tank unsecured or put stress on a carrier that was not designed for its loaded weight. The RDS products are a different category: they are large truck tank-and-toolbox combinations, with stated dimensions from 52 to 55 inches long.
Their listing says universal fit, but that does not mean universal spare-tire mounting. Confirm attachment points and clearance before selecting any of these options for this use.
Fuel restrictions can rule out a tank regardless of capacity
A tank’s stated capacity does not tell you which fuel it can safely hold. The RDS 72746, 72772, and 72773 descriptions explicitly say not for use with gasoline, a decisive restriction for buyers seeking a gasoline reserve. The JSD listings use gas-tank wording in their titles, but the supplied specifications do not identify approved fuel types or explain whether they are intended for storage, transfer, or a particular fuel system.
Do not infer compatibility from the product name alone. Confirm the intended fuel, fittings, venting requirements, and applicable vehicle and transport rules with the manufacturer or a qualified installer.
This is especially important when choosing between a compact JSD tank and a larger RDS tank: a bigger capacity cannot compensate for a fuel restriction or an installation that is not approved for your intended use.
How to Choose a Spare-Tire Fuel Tank
Capacity and tank format
Choose capacity by deciding how much reserve fuel you actually need and how much space the tank can occupy. The JSD round tanks range from 5.5 gallons for the M223 to 8 gallons for the M271 and 15.88 gallons for the M311. The RDS toolbox tanks list 41 gallons for the 72773 and 90 gallons for both the 72746 and 72772.
The round JSD products are the closer format for a compact auxiliary installation, while the RDS tanks are large truck-bed combinations. A buyer prioritizing a smaller round tank should start with the 5.5- or 8-gallon options; a truck user seeking substantial auxiliary capacity can compare the RDS models, subject to their fuel restriction.
Dimensions, weight, and available mounting space
Check the tank’s listed size and weight against the vehicle and intended mounting point before choosing. The RDS tanks weigh 87 to 120 pounds and provide dimensions: 52 x 21 x 19 inches for the 72746, 55 x 24 x 22.25 inches for the 72772, and 55 x 18 x 21.75 inches for the The JSD tanks weigh 8.9 to 15.8 pounds; their titles identify sizes of 8 x 26 inches, 10 x 24 inches, and 12 x 33 inches.
Those figures do not certify spare-tire fit. A buyer with limited space should investigate the smaller JSD formats first, while anyone considering a heavier tank needs to confirm that the mounting structure can support its filled load.
Vehicle fit and included mounting parts
Look for a stated vehicle fit and identify exactly what hardware comes with the tank. The RDS listings identify trucks and say universal fit, but describe toolbox combinations rather than spare-tire mounts. The JSD M223 and M311 specify car compatibility and include two brackets, a cap, and a housing; the M271 lists cars and trucks and includes two brackets in its features.
These details help compare general vehicle scope and included parts, but none verifies a specific spare-tire carrier or installation. A buyer wanting a round tank with brackets can focus on the JSD options, then confirm bracket attachment and vehicle clearance.
A truck owner wanting an integrated toolbox may consider RDS, while checking the intended fuel and installation requirements first.
Which Tank Fits Your Spare-Tire Setup?
For a compact round auxiliary tank, start with the JSD AUTO PARTS M223: it holds 5.5 gallons and includes two brackets, a cap, and a housing. If you need more capacity in a similar round format, the JSD AUTO PARTS M271 offers 8 gallons and lists cars and trucks; the JSD AUTO PARTS M311 raises capacity to 15.88 gallons. None is confirmed as a direct spare-tire mount, so verify fit and attachment before choosing.
For a truck-bed tank-and-toolbox arrangement rather than a spare-tire installation, consider the RDS MFG INC 72773 at 41 gallons or the 90-gallon RDS MFG INC 72746 and RDS MFG INC The RDS descriptions explicitly prohibit gasoline use, so check fuel compatibility before considering them.
Related Buying Guides
Frequently Asked Questions
Can any of these tanks mount directly to my vehicle’s spare tire?
None of the listings confirms direct spare-tire mounting or compatibility with a specific vehicle. The JSD round tanks may suit a spare-tire-style installation, but check their dimensions and attachment method against your vehicle. The RDS options are described as truck-bed tank-and-toolbox arrangements, not confirmed spare-tire mounts.
Which fuel types are compatible with each tank, and can the tank be used to transfer fuel?
The JSD listings call their products gas tanks, but confirm the intended fuel with the seller before use. The RDS descriptions explicitly prohibit gasoline, so do not use those tanks for it. The listings do not establish transfer capability or provide enough detail to confirm compatible fuels for every tank.
What mounting hardware, hoses, and fittings are needed for a complete installation?
Check each listing and confirm the full installation requirements before ordering; the provided details do not specify every hose, fitting, or mounting component. The 5.5-gallon JSD includes two mounting brackets, a cap, and a housing, while the 15.875-gallon JSD title mentions brackets. Do not assume other hardware is included.
How should I choose between the JSD round tanks?
Choose by required capacity and confirmed fit: the M223 holds 5.5 gallons, the M271 holds 8 gallons, and the M311 holds 15.88 gallons. The M271 listing mentions cars and trucks, but that does not confirm a particular fit. Verify dimensions, mounting, and fuel compatibility before selecting any option.
What should I verify before choosing an RDS tank?
Confirm that its truck-bed tank-and-toolbox arrangement suits your vehicle, and check the installation requirements and intended fuel. The RDS descriptions prohibit gasoline use. The 72773 is listed at 41 gallons, while the 72746 and 72772 are listed at 90 gallons; the provided details do not confirm spare-tire mounting.
Final Words
For a compact, round auxiliary tank, the JSD M223 is the strongest match in these listings: it holds 5.5 gallons and includes two brackets, a cap, and a housing. Consider the 8- or 15.88-gallon JSD options if you need more capacity. None is confirmed as a direct spare-tire mount, so verify dimensions and attachment first.
Choose an RDS tank for a truck-bed setup only after confirming fuel compatibility; its description prohibits gasoline.
