So sitting here literally with nothing to do I started thinking (this has been know to he hazardous) about what I could do with my truck.

I never leave the spare tire on a pickup underneath the truck. Around here flat tires are common and so I just leave it in the back of the truck. Since I don’t have the tire under there or the crank (took it out so it doesn’t rust and bind up if I ever want to put tire back under there.)
Why couldn’t I put a second gas tank in that spot?
Would it meet DOT regs? I mean it would be inside the frame on both sides and in front of the bumper seems like it would be plenty safe. I was thinking I could get a 36 gallon Bronco gas tank and put in there

So tell me why this would be a bad idea.

No I don’t want to hear about if I wanted better mileage I should have bought a diesel it’s not about mileage it about having enough gas to get where I want to go with out messing with Jerry cans

 

seems possible to me with the aid of an electric fuel pump. You would just need a switch to change tanks.

Maybe a ball valve to switch it over and then hit an upfitter switch to activate the pump and fuel guage?

 

This question comes up once in a while. Haven't seen anyone actually do it yet. But what you want to investigate is putting the Excursion tank in there. It's a 40 gal IIRC, and the frame mounting holes might even be there.

 

That's where the 2nd tank used to be on older Ford trucks. I had a 1985 Ford F250 6.9 diesel with 2 tanks; one of them was in the position you described and the other was a saddle tank in front of the driver side rear wheel like the current tanks.

Mike

 

I thing Excursion frame ends and Superdutys are different--the underframe receivers don't interchange. Maybe Transferflow has tanks that go between the frame rails?

 

Instead of all the fitting issues why not just use a fuel cell like I have used on some of my previous hot rod type cars.
They come made of steel, aluminum, plastic, they have all kinds of fuel fill and mount setups.
You can get a 32 gallon for about $250.00

 

The problem I see is filling it. Anytime you add another tank, you gotta think out the plumbing, both how it's coming out and how it's geting in. As for the switch-over between tanks, I don't see a problem there. Lots of hot rods run two small tanks and pickups have done this for years. I would think you could simply add a pump, and the switch and be done with it.

 

It would work fine. Ford ran this setup on previous generation F-series. My 1995 F-150 had dual tanks.

If you found a 1995 F-Series (or older) truck in the wrecking yard, strip off the fuel tank switch, fuel line solenoids and the associated wiring. Install the switch and the solenoids, throw in a rear tank that will fit. (Make sure the tank has a fuel level sender compatible with your stock fuel gauge.) You now have dual fuel tanks with a factory looking switch to select the tank. (The fuel gauge would also the level of the tank selected).

 

A better approach would be to contact Titan tanks and install one of theirs, which is model specific to your truck. Installs in about 2 hours. Transfer Flow also has some options. There is an aftermarket OEM mid-frame tank available that has all the necessary approvals, but is costlier than the Titan and requires plumbing, switching, etc.

 

The Titan fuel tanks are designed for diesel applications only. Also, Titan only offers tanks for the SC and CC trucks. I received confirmation of this last year when I inquired about my application.

Ford Large Capacity Diesel Fuel Tanks for Pickup Trucks ~ TITAN Diesel Fuel Tanks: The Leader in Aftermarket Fuel Tanks

The OP may want to consider using the 40 gallon OEM fuel tank used on the "chasis" SD trucks. This tank is not mounted "midship" but where the spare tire is stored. He may be able to find a wrecked truck and find everything he needs (tank, mounts, fuel pump, wiring, plumming, etc). See Page 38 in the link below:

https://www.fleet.ford.com/truckbbas...0-550_08bb.pdf

 

Would the fill neck be plumbed into the bed? I'd be leary of having an exposed neck where my load could damage it. I'm pretty sure no one in there right mind is going to have a body shop create a second fuel door on the bedside. Maybe a flip-down license plate fill location if the spare is gone anyway???

 

It's worthiness all depends on how big a tank you can fit in there...

 

If you are talking about your 2008 truck there are a couple of reasons why you will not find an aux tank setup for your truck. First, the emmissions canister will not handle it, and second the truck pressurizes the fuel tank from time to time and checks for leaks. I know this sounds crazy, but I went through this on mine. The computer will throw a code on the cel if it senses a leak in the fuel system, [ this is why it does it with a loose fuel cap] when mine did it I could not put fuel in the tank, some kind of valve or something must close. I had a 100 gal aux tank on my last truck and wanted to add it to this truck and when I hooked it up and cut into the fuel neck hose to add the lines it would trip the cel and give me crap. I am not saying that I did this, but a potential alternative could be to get two 12 volt solenoid valves and add them to the fuel transfer lines and energize them only when the transfer pump is on. {they have them on e-bay for about 20 or 30 bucks}. The cel will trip now and then, but if you have a tool you can just re-set it. An acceptable compromise to have the luxury of an additional 100 gals. of fuel. Ther are some after market tanks available for your truck, but nothing very much bigger than you have now. P.S. the fuel system canister is above the spare tire on my truck, I have an in the bed tank.

 

Good questions... Here is a pic of a 2010 F550 with "aft-of-rear" fuel tank.

 

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