You would connect an auxiliary conversion kit from the auxiliary tank to your existing fuel line for the vehicle you have. These kits would have a ball valve that allows the fuel from the auxiliary tank to the original tank when needed. They can be left on all the time, provided it gets daily use. It should not sit for an extended amount of time in the auxiliary tank to allow the fuel to degrade. The fuel would not run out the filler cap after the main truck tank is full.
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RDS Aluminum Auxiliary Fuel Tank Toolbox Combo, 90-Gallon, Rectangular, Black Diamond Plate, Fuel Filler Shroud, Model# 72745PC

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Shipping:
Free shipping (lower 48 states) - Factory shippedHeavy/large item. Lift gate service available.
Store Pickup:
Not available - online only
- Low profile design works well with fifth-wheels
- Built-in baffles reduce fuel sloshing during transport
- Rust-free aluminum construction protects fuel from contamination
- Sight gauge allows you to quickly determine fuel level
- For use gravity feeding fuel into OEM tanks
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Description
Key Specs
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Product Summary
What's Included
- (1) Auxiliary fuel tank/toolbox combo
Features + Benefits
- Low profile design works well with fifth-wheels
- Built-in baffles reduce fuel sloshing during transport
- Rust-free aluminum construction protects fuel from contamination
- Sight gauge allows you to quickly determine fuel level
- For use gravity feeding fuel into OEM tanks
- Large 2in. fill spout allows for faster fill-ups and siphon-free storage
- 3/8in. FPT drain plug
- 100% pressure tested and leak-free
- Can be used as an auxiliary tank
- Safety vent prevents fuel spillage while venting
- Includes 3/8in. coupling for pickup
- Secure fill compartment helps prevent theft
- Extra fuel capacity allows for increased driving range
- Simple installation can be done in as few as 30-40 minutes
- Diesel install kits are available (Item#s 3490901, 3490902, 43748, sold separately)
Key Specs
| Attribute | Specification |
|---|---|
item# | 51671 |
Brand | RDS |
Manufacturer's Warranty | 1 year limited warranty |
Ship Weight | 184.0 LB |
Capacity | 91 Gal |
Shape | Rectangle |
Material | Aluminum |
| Attribute | Specification |
|---|---|
Finish | Powder-Coat |
Inlet Port | 2 in |
Outlet Port | 2 in |
Mounting Hardware Included | Yes |
DOT Approved | Yes |
Product Weight | 131 lb |
Reviews
Questions & Answers
Questions
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· 11 months ago
Can this tank be left on all the time. Will fuel run out the filler cap after the main truck tank is full?
1 answer-
ProductExpert6· 11 months ago
Helpful?
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· a year ago
What are the dimensions of the tank?
1 answer-
ProductExpert6· a year ago
The dimensions are 55" L x 31" W x 19.5" H.
Helpful?
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· 6 years ago
Can this be used as a transfer tank as well? i.e. is there room next to the fill spout and is it plumbed to install a 12 volt pump?
1 answer-
ProductExpert6· 6 years ago
This can only be used as an auxiliary tank. It does not have provisions to use as a transfer tank. See our recommendation, item #47057 that can be used as an auxiliary or transfer tank.
Helpful?
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· 8 years ago
Aside from whether it fits or not, I will measure it to be sure, but is it safe to use these under tonneau covers?
1 answer-
ProductExpert9· 8 years ago
These tanks can be used under a tonneau cover with the use of a hose vented outside the bed allowing fumes to escape.
Helpful?
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Warranty
Manufacturer's Warranty
1 year limited warranty
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Specifications
91 Gal
110 Gal
77 Gal
110 Gal
Rectangle
L-Shaped
Rectangle
Rectangle
Aluminum
Steel
Aluminum
Aluminum
Powder-Coat
Powder-Coat
Diamond Plate
Powder-Coat
2 in
2 in
-
-
2 in
1/4 in
-
-
Yes
Yes
No
No
Yes
-
Yes
Yes
131 lb
165 lb
72.0000 lb
132.0000 lb
-
-
Aluminum
Black
-
-
60.0 x 21.0 x 22.0 in
51.0 x 24.0 x 27.0 in
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