Pairing an auxiliary fuel tank is a great way to extend the fuel capacity of your RAM truck. The challenge is finding the right size tank to maximize your additional fuel capacity that also fits securely inside your truck.
This article will highlight the key RAM pickup bed dimensions that you need to know in order to find the right sized auxiliary fuel tank or transfer tank. We will then highlight a few of the best auxiliary fuel tanks and transfer tanks that will fit inside your RAM pickup bed.
Top Auxiliary Tanks for RAM Short Beds:
- ATI Auxiliary Tank (Ships by UPS): Click here to see it.
- Transfer Flow Auxiliary Tank: Click here to see it.
Top Auxiliary Tanks for RAM Long Beds:
- ATI Auxiliary Tank (66 Gallon): Click here to see it.
- Transfer Flow Auxiliary Tank (75 to 100 Gallon): Click here to see it.
RAM Short Bed vs RAM Long Bed
- RAM short bed trucks have a pickup bed length that ranges from 5 foot 7 inches (67 inches) to 6 foot 4 inches (76 inch).
- RAM long bed trucks have an 8 foot (96 inch) pickup bed length.
Truck Bed Dimensions vs Auxiliary Fuel Tank Dimensions
When measuring your pickup bed for a fuel tank, the fuel tank dimensions will be opposite of the pickup bed dimensions.
- Pickup Bed width equals fuel tank length
- Pickup Bed length equals fuel tank width
- Pickup Bed depth equals fuel tank height
RAM 1500 Pickup Truck Bed Specs
RAM 1500 5 foot 7 inch Pickup Bed Specs
- Factory Fuel Capacity: 26 gallons
- Pickup Bed Width: 66.4 inches
- Pickup Bed Wheel Well Width: 51 inches
- Pickup Bed Length: 67.4 inches
- Pickup Bed Height: 21.4 inches
RAM 1500 6 foot 4 inch Pickup Bed Specs
- Factory Fuel Capacity: 26 gallons
- Pickup Bed Width: 66.4 inches
- Pickup Bed Wheel Well Width: 51 inches
- Pickup Bed Length: 76.3 inches
- Pickup Bed Height: 21.5 inches
RAM 2500 Pickup Truck Bed Specs
RAM 2500 6 foot 4 inch Pickup Bed Specs
- Factory Fuel Capacity: 31 gallons
- Pickup Bed Width: 66.4 inches
- Pickup Bed Wheel Well Width: 51 inches
- Pickup Bed Length: 76.3 inches
- Pickup Bed Height: 20.2 inches
RAM 2500 8 foot Pickup Bed Specs
- Factory Fuel Capacity: 32 gallons
- Pickup Bed Width: 66.4 inches
- Pickup Bed Wheel Well Width: 51 inches
- Pickup Bed Length: 98.3 inches
- Pickup Bed Height: 20.2 inches
RAM 3500 Pickup Truck Bed Specs
RAM 3500 6 foot 4 inch Pickup Bed Specs
- Factory Fuel Capacity: 31 gallons
- Pickup Bed Width: 66.4 inches
- Pickup Bed Wheel Well Width: 51 inches
- Pickup Bed Length: 76.3 inches
- Pickup Bed Height: 20.1 inches
RAM 3500 8 foot Pickup Bed Specs
- Factory Fuel Capacity: 32 gallons
- Pickup Bed Width: 66.4 inches
- Pickup Bed Wheel Well Width: 51 inches
- Pickup Bed Length: 98.3 inches
- Pickup Bed Height: 20.2 inches
How to Measure a Fuel Tank for a RAM truck with a Fifth Wheel
When you have a fifth wheel in your RAM truck, this will impact the available width of your auxiliary fuel tank. If the auxiliary fuel tank has too much width, it will potentially interfere with your fifth wheel.
When you have a fifth wheel, you need to measure from the back of your pickup bed to the point when you run into the fifth wheel. This measurement will be the amount of available width you have to accommodate an auxiliary fuel tank or transfer tank in your truck bed.
How to Measure RAM Wheel Wells for an Auxiliary Fuel Tank
All RAM pickup trucks have a pickup bed width of 66.4 inches. This means that an auxiliary fuel tank could have up to 60 inches of length and fit comfortably inside your pickup bed.
The problem is that once the width of your auxiliary fuel tank hits the wheel well, your available pickup bed width rapidly declines from 66 inches to just 51 inches.
This means that if your auxiliary fuel tank is too wide, the available length of your fuel tank can not exceed 51 inches or it would not fit between the wheel wells in your truck bed.
- Make sure you know the exact measurement from the back of your pickup bed to where you first hit the wheel wells. This measurement will tell you the maximum tank width you can have before hitting your wheel wheels.
How to Work Around Wheel Well Limitations
There are a few ways to work around length limitations caused by your wheel wells.
- Keep your auxiliary fuel tank width less than the width from the back of your pickup bed to the point where your wheel well starts. Narrow Auxiliary Fuel Tanks and Narrow Transfer Tanks are designed with minimal width sizes.
- Choose Auxiliary fuel tanks with notches at the bottom of the tank. The tank notches reduce the lower fuel tank length and are designed to fit in between wheel wells in your truck bed.
How to Measure an Auxiliary Fuel Tank for a RAM Truck with a RamBox?
The RamBox Cargo Management System option is available on the 5ft 7in and 6ft 4in pickup beds for the following RAM truck models:
- RAM 1500 - regular cab, crew cab, and quad cab
- RAM 2500 - crew cab and mega cab
- RAM 3500 - crew cab and mega cab
If your RAM truck has a RamBox, this will reduce your truck bed space width to approximately 49 inches at the most narrow point.
- If you have a RamBox, it is very important for you to measure the truck bed width because this will directly influence the amount of fuel tank length you can accommodate in your truck.
RAM 1500 / 2500 / 3500 Auxiliary Fuel Tanks for Short Beds
- Ram trucks with a short bed truck typically have a maximum width of up to 16 inches before they hit the wheel well.
- That means auxiliary fuel tanks with a width of greater than 16 inches will not be able to fit in a short bed truck unless the tanks have a notch that reduces the length to 51 inches or less.
Note: Be sure to measure the width from the back of your pickup bed to the where the wheel well starts. You may have other equipment or items in your truck that change the measurements of what you need.
Auxiliary Fuel Tanks for RAM Short Beds
ATI offers a rectangular aluminum diesel auxiliary fuel tank that connects to your factory fuel tank using the Fuel Shotz system. The following tank sizes have maximum widths of 16 inches or have notches that with a maximum length of 51 inches.
- AUX41R: 41 Gallon: 48.5 inches long by 11 inches wide by 19 inches high
- AUX43R: 43 Gallon: 51 inches long (notched) by 12 inches wide by 16.5 inches high
- AUX46R: 46 Gallon: 57 inches long by 12 inches wide by 16.5 inches high
- AUX51R: 51 Gallon: 55 inches long (notched) by 9 inches wide by 9 inches high
Check other 40 gallon auxiliary fuel tank options.
Transfer Tanks for RAM Short Beds
The following DOT Approved rectangular aluminum transfer tanks are designed to fit a RAM short bed truck:
- TTR38: 38 Gallon: 48.5 inches long by 11 inches wide by 19 inches high
- TTR43: 43 Gallon*: 58 inches long by 12 inches wide by 16.5 inches high
- TTR46: 46 Gallon: 57 inches long by 12 inches wide by 16.5 inches high
- TTR51: 51 Gallon**: 60 inches long by 9 inches wide by 24 inches high
- TTR58: 58 Gallon: 58 inches long by 21 inches wide by 13 inches high
*The 43 gallon size has a notched bottom length of 51 inches.
**The 51 gallon size has a notched bottom length of 55 inches.
Check all ATI transfer tanks for more options.
Transfer Tanks for RAM 1500 5ft 7in Bed
Unfortunately, Transfer Flow does not offer auxiliary fuel tanks that are designed to fit the RAM 1500 5ft 7in inch bed. Transfer Flow does offer multiple transfer tanks that will fit the RAM 1500.
Note: Transfer Flow Transfer Tanks do not transfer fuel directly into your truck fuel tank. The transfer tanks are designed as a portable fuel source that can be dispensed with a transfer pump.
Diesel Refueling Tank
- 070TK34311: 80 Gallon: 47 inches long by 23 inches wide by 25.75 inches high
Transfer Tank with Pump
These tanks are DOT approved to carry diesel, gas, methanol, ethanol, and kerosene.
- Buy Tank: 40 Gallon: 40 inches long by 23 inches wide by 17.5 inches high
- Buy Tank: 82 Gallon: 47.75 inches long by 22.63 inches wide by 27 inches high
Fuel Tank with Transfer Pump
This split tank is DOT approved and allows you to carry two different fuel types in the same tank. The dual tank design provides two separate containers to carry each fuel type. The tank includes dual fuel transfer pumps, one for each fuel compartment.
- Buy Tank: 100 Gallon (50 gal / 50 gal split): 47.38 inches long by 31 inches wide by 24.19 inches high
Transfer Tanks for RAM 1500 6ft 4in Bed with RamBox
RAM trucks with a slightly larger 6ft 4in pickup bed can fit all the Transfer Flow tanks listed for the 5ft 7in beds as well as two additional fuel tank sizes:
Diesel Refueling Tanks
- Buy Tank: 50 gallon: 54 inches long by 15.5 inches wide by 23.1 inches high
Refueling Transfer Tank with Pump
- Buy Tank: 50 gallon: 54.38 inches long by 15.5 inches wide by 24.5 inches high
Transfer Tanks for 1500 RAMBox Trucks
Because of the reduced bed width of the RamBox, Transfer Flow only has two transfer tank options that will fit a RamBox:
Refueling Transfer Tank
- Buy Tank: 40 Gallon: 40 inches long by 23 inches wide by 17.5 inches high
Split Refueling Tank
- Buy Tank: 100 Gallon (50 gal / 50 gal split): 47.38 inches long by 31 inches wide by 24.19 inches high
Auxiliary Fuel Tanks for RAM 2500 / 3500 6ft 4in RamBox Trucks
If you have a 2500 RamBox truck, you can fit all the Transfer Flow transfer tanks listed in the 1500 RamBox size, plus the following auxiliary fuel tank:
Note: this fuel tank size will also fit a RAM 2500 6ft 4in bed with a 5th wheel hitch without covering the 5th wheel holes.
- Buy Tank: 40 Gallon: 48 inches long by 19 inches wide by 19.38 inches high
Compare all Transfer Flow 40 Gallon Tanks.
Auxiliary Fuel Tanks for RAM 2500 / 3500 with 6ft 4in bed
The Auxiliary fuel tanks that will fit are dependent on whether or not you have a fifth wheel hitch. Also some of these tanks would cover some of the holes of the 5th wheel hitch
Have a 5th Wheel Hitch & Tank will cover some 5th wheel holes:
Auxiliary Fuel Tanks
- Buy Tank: 50 Gallon: 60.75 inches long by 18.5 inches wide by 18.25 inches high
- Buy Tank: 75 Gallon: 60.75 inches long by 20.5 inches wide by 22.75 inches high
Note: the Transfer Flow Auxiliary Fuel Tanks include a notched lower length that reduce the bottom tank length.
Compare additional 50 gallon auxiliary tank options.
Auxiliary Fuel Tanks for RAM 2500 / 3500 with 8ft bed
2500 RAM trucks with an 8ft bed would be able to fit all auxiliary fuel tank sizes listed for the lower bed sizes as well as this larger size:
- Buy Tank: 100 Gallon: 60.75 inches long by 26.75 inches wide by 22.75 inches high
Compare other 100 gallon auxiliary fuel tank options.
Auxiliary Fuel Tanks for RAM Short Bed Trucks
Fuelbox auxiliary fuel tanks are highly customizable and are designed for diesel fuel only. The following auxiliary fuel tanks are designed to fit a RAM short bed.
- FT47: 40 Gallon: 62 inches long by 10 inches wide by 19.5 inches high
- FT50: 50 Gallon: 60 inches long by 16 inches wide by 15 inches high
Auxiliary Fuel Tanks for RAM Long Bed Trucks
Long bed Ram trucks can fit all tank sizes that fit in a short bed truck as well as the following larger sizes:
- FT70: 70 Gallon: 48 inches (notched) long by 19 inches wide by 19.5 inches high
- FT90: 85 Gallon: 53 inches (notched) long by 25 inches wide by 19.5 inches high
Compare all Fuel box tanks to check options available.
Auxiliary Fuel Tanks for RAM Short Bed Trucks
ATTA offers a rectangular aluminum diesel auxiliary fuel tank that connects to your factory fuel tank using a proprietary fuel system. The following tank sizes have maximum widths of 16 inches or have notches that with a maximum length of 51 inches.
- AL40RU: 40 Gallon: 54 inches long by 10 inches wide by 18 inches high
- AT45RBR: 45 Gallon: 60 inches long by 12 inches wide by 15 inches high
- AT50RU: 50 Gallon: 60 inches long by 12 inches wide by 18 inches high
Compare all ATTA auxiliary fuel tank options.
Wedge Auxiliary Fuel Tank for RAM Short Bed Trucks
- AT50W: 50 Gallon: 60 inches long by 15 inches wide by 18 inches high
For tank options, see our full Auxiliary Fuel Tank selection.