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Old 08-22-2018, 06:09 AM   #21
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If you’re looking at additional fuel storage for your truck you’ll no doubt run into both transfer tanks and auxiliary fuel tanks, and often there is a pretty big price difference even though they look pretty similar. So what’s causing the price difference and which one do you need?

Transfer Tanks are for the transfer of fuels. This could be bringing extra fuel on a trip to fill up an ATV, or maybe you’re in construction and need to top off a generator. They are primarily used for diesel but depending on the manufacture you can find tanks that are certified for other fuels. The big difference is between a transfer tank and an auxiliary tank is that the transfer tank has to have the fuel pumped out, but this can be pumped to your truck's fuel tank. But in order to transfer the fuel you will need a transfer pump. These are available as manual units where you either turn a crank or pump a handle or as 12 volt electric units that do the work for you. These pumps will add anywhere from $90 to $350 to your total expenditure.

Auxiliary Tanks are plumbed right into your stock factory tank. This is sometimes accomplished with the aid of a small 12v pump or gravity fed. Tanks almost always have a shut off valve so you can stop the flow of fuel if necessary or it wanted. Since the a lot of the connections will be made under the trucks cargo floor you’ll want to make sure your tank and lines are sealed properly and free of leaks. With an electrical pump in your system, you would typically just keep an eye on your factory fuel gauge and when you wanted to refill, you would just flip the switch you would have mounted inside your truck and refill the tank as you roll down the road. If you use a gravity fill system, gravity will simply replace fuel into your factory tank as your engine consumes fuel. Because of the danger that you could forget to turn your electric pump off while filling and consequently overfill your tank, electric assisted pumps should have a return line installed to direct overfill back into the auxiliary tank.

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Old 08-22-2018, 06:48 AM   #22
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keep it simple, replace your oem tank with a titan tank....keeps more room in the box.
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Old 08-22-2018, 11:01 AM   #23
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Again, contrary to Bad Moon's info, gravity feed from an auxiliary tank is not illegal nor dangerous. As mentioned earlier, his info comes from an industry source; someone in the business of selling overpriced systems by misrepresenting facts and law. (Transferflow.com) We use an auxiliary tank that feeds fuel by gravity that has worked fine for years at a small fraction of the cost of what Moon is pushing. If you plan to install an aux fuel system and never look at again, maybe you should go with a high priced transfer system but most people inspect and maintain their equipment regularly.
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Old 08-22-2018, 11:26 AM   #24
GreG L.
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This subject is allot line truck towing ability. If you feel safe with a gravity feed system then get one, if it bothers you get a transfer system. Transfer cost more, you are paying for safety, convenience and all your truck features working. As for illegal I only know about CA, I am sure there are others, but who is going to check. Google is your friend.
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Old 08-22-2018, 12:02 PM   #25
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just went to the Deezee website and lifted this from their Auxiliary tank fuel connection kit. Looking at it is looks like the shut off valve goes where the drain goes. Same chance of leak as a drain plug. Since the gravity feed is not supposed to be used while vehicle is in operation I would think most safety concerns would be satisfied.


Shut-off Valve to Start and Stop Diesel Fuel Transfer
Flow Valve Must be Closed During Vehicle Operation
Gravity System Not Intended for Continuous Fuel Transfer
Only For Use With Transfer Tanks Meeting Federal DOT Requirements

Disclaimer-- no connection with any fuel tank manufacturer or re-seller.

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Old 08-22-2018, 10:31 PM   #26
Dam Worker
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My new truck has a 48 gallon fuel tank which seems to be more than enough right now to get me where I need to go and not worry about running low on fuel. Probably have to stop for some bathroom breaks way before I need fuel. Maybe later when doing more extensive traveling I may need to add additional capacity.

Tom Marty
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Old 08-26-2018, 07:46 AM   #27
Jersey Devil
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Originally Posted by Texan View Post
I would think if it is illegal then the many manufactures of auxiliary tanks would have a visit by the feds. Never the less, i have had the RDS 60 gal. auxiliary fuel tank for 6 years and it has worked great. I would recommend a extra or larger tank to anyone who wants to stay out of the truck stops or interstate fuel stations with there RV. As for Jersey Devil the Titan seems to have a good reputation and i would go for it. The positives way out weigh the negatives.
Thanks appreciate your info.
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