Putting dual tanks on c20

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nathanpotts

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I have a 84 c20 and the tank was already moved one time for a dump bed. I am ready to make it back to original but now I’m thinking about putting on dual tanks. What does this require for mods to the truck? What parts do I need and does any company make new tanks and other equipment for the tanks? ( sending units) sorry if this is a dumb question I’m new here
 

bucket

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Tanks and sending units are available new. Not sure about mounting brackets, but they aren't too hard to find used.

There's more than one way to skin that cat. You can do a factory type setup, you can modify the tanks for a large crossover tube (essentially making them one) or you can install a 12v transfer pump and fill the main tank as needed, with the flick of a switch.
 

REVINKEVIN

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Hey. Where do you live? I am about to take everything dual tank related off of my truck to install a single rear mount tank. I even have a new valve for the dual tanks.
 

fast 99

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It can be done fairly easily. Of course, need a tank, sender brackets, ect.

What I used an electric 5 port, single terminal change over valve and installed a 6-terminal on-off-on switch in the dash area. Tapped into the wiring behind the cluster for the gauge and power from fuse panel. Use one side of the switch for the valve and other side for gauge.

Only problem doing it this way is if the power to the switch was lost. If the valve happened to be energized to a full tank and the other one was empty, it will go to the empty tank. I used that truck for 200k this way and never had an issue. Just need to be careful wiring it up.


Another option is using a factory change over valve, but I decided not to do it that way because it required much more wiring back to the valve, a factory dash switch, related wiring, and cutting a hole for it. If a donor vehicle is available, the parts could be harvested.
 
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nathanpotts

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Hey. Where do you live? I am about to take everything dual tank related off of my truck to install a single rear mount tank. I even have a new valve for the dual tanks.
I’m in pa
 

nathanpotts

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Tanks and sending units are available new. Not sure about mounting brackets, but they aren't too hard to find used.

There's more than one way to skin that cat. You can do a factory type setup, you can modify the tanks for a large crossover tube (essentially making them one) or you can install a 12v transfer pump and fill the main tank as needed, with the flick of a switch.
How would you use a crossover tube? Making it one would only require equipment for one tank to get gas to the carb?
 

bucket

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How would you use a crossover tube? Making it one would only require equipment for one tank to get gas to the carb?

You would have to weld threaded bungs onto the tanks for a crossover tube/hose. But yeah, you would only need to draw from one tank. You could fill from either side too if the crossover is adequately sized.
 

nathanpotts

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Okay and what is needed for a transfer pump setup?
 

oldretiredafguy

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There is an post from earlier this year that has a member's solution for filling both tanks from either side:

 

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