So I came across a deal on a 90 gallon L shaped auxilary fuel tank to mount in the bed of the truck. It's used but still good. I have never had one nor mounted one in a truck. I was wondering if someone on here has had one and mounted it. Any tips on how to do so? 

 Also, if you have one are you gravity feeding it to the main tank or did you install an inline fuel pump? I have a small inline pump on the shelf and was thinking about using it with this tank to fill the main tank with a flip of a switch. Thoughts??

 I'll be getting the tank sometime over the weekend so I'll post up pics once I have it.

 Thanks for any input.

I've been debating doing the same thing but I'm concerned with a short bed and loosing the room to the tank. A switch would be nice so you could get to 1/4 - 1/2 tank and then fill it back up (as long as you remember to turn it off in time!). You might look at Transferflow.com's website to see what options they offer with their tanks in terms of how they fill from one tank to the other. 

 I'll check out transferflow, thanks! A friend of mine had an inline pump on his. He did forget to cut it off once. But only once. He had fuel coming out of the filler cap and down the side of the truck. 

Edited May 23, 2024May 23 by Doubletrouble

I’m sure there’s a cool way to rig up a float switch to automatically have your 12v pump come on to keep your tank filled, but the gravity feed kits from RDS seem to be pretty good. Ours is the first one, the one that fits the 99’ Fords.

 

https://rdsaluminum.com/rds-parts.html

 I'm  considering the gravity feed as well. Not sure which way I want to go just yet. It would be cool to just flip a switch and start transferring fuel. On the other hand, gravity feed is a pretty simple setup, no worries about a pump failure.

Edited May 24, 2024May 24 by Doubletrouble

Look up dual tank control valves. You should be able to get either a manual or electromechanical valve for controlling fuel on a stock set up. Now AirDog / FASS is tougher with 1/2 inch lines. 

 

Just consider gravity setups it's possible to over fill if you forget to shut the valve.

 Finally have pics of the auxilary tank for those of you that are interested. 

 

 

 

 

 I need to clean it up, maybe polish it and make it shine again. Then test it for leaks. I was told it does have a small leak on the driver's side (as the tank is installed) so I'll have to look into that.

If it were me I would use that in line pump you have on the shelf. Grab a float sensor like snow uses in the water meth kits. Wire it into a relay with the float switch being wired into the relays coil circuit and mount it in your oe fuel tank. This way the system is autonomous and shuts off with the float valve. You can wire in multiple floats for peace of mind and wire in a led of your choosing so you can tell the pump is running.