nope,
not enough room under there for more tanks.

it holds 44 gallons now, just how far from a gas station are you going to wander?
I can go 600 miles if I want to push it.

I always get more diesel at 2-3 hours of driving, or close to a half tank at worst.

I made the mistake just once, of pushing it too far.
mine has a Sump and it will suck the very last drop out.

 

I have a side rail tank on my excursion but it is not a factory tank. This truck originally had a veggie stroke kit and the tank was part of that. The veggie stroke kit has long been removed and I plan to convert it to work exactly as you're discussing.

 

I guess from an older( approaching 75 ) perspective.... How many hours you going to drive without a bathroom break ??!

I get the fuel discount angle... I do Kroger discount of like $1.25 per gallon, but it has a 35 gallon limit Still $40 off makes me smile.

Even on occasion have taken cans when filling up my F250, so can get every penny of that discount!

Wish they gave that discount in cash back... so I'd have more beer money wife wouldn't know about !

 

I agree with MoBill122, where are you going that 44 gallons of fuel is not going to get you to a gas station. I am in my 60’s and lucky if I don’t have to stop every 2 1/2 to 3 hours but I guess if you’re doing some long term camping it couldn’t hurt.

 

I did an all day drive yesterday, from my home in Oklahoma to my son's home in Georgia.

Drove the Kia Amanti, which when full of gas, the dash show 390 miles remaining.

I had to stop at 200 miles remaining, to drain my tank....
it is pointless to fill up a 1000 fuel tank, when your own body can't last more than 2 or 3 hours w/o a break.

I used to have a '98 Dodge diesel truck, it had a 110 spare fuel tank in the bed, with one of those Automatic transfer systems, add in the 34 gallon seat tank, and 20 mpg, there is no way, in hell, you can drive that far w/o finding a fuel station.

Maybe up in Alaska, or down in Auzzie land, but not here in the states.

my Excursion has a 44 gallon tank, with a Sump on it, and I know for a fact, that the 7.3L can slurp up 43.333 gallons of diesel before it dies.... did that one night on an Emergency run, dull brain cells not watching the fuel gauge.

 

I run a second tank (01 7.3l, 205k mi). Its an aftermarket one for a vege conversion. Not nearly as nice as some of the better ones but it adds another 24 gal. I use that as the daily tank, and then fill the stock one when needed. It came with the vehicle... but i would be adding a second tank of it didnt. Probably wouldnt use this kit, but it does work and isnt priced too high. The tank seems really strong and is metal. Doesnt sit too low (sits just above the hump of the transfer case). The piping is scabby but does work. You can switch tanks on the fly. The heated fuel lines work great as it can get effing cold where i am (i have to plug it in to start it, its that cold). Also adds options for better filtration.

My personal best is 850miles more or less unloaded (at the time, this was a little over a month without refueling). Both tanks were pretty low and the wind was probably in my favor. Nut behind the wheel is also well adjusted for this to happen. Probably around 60gal of diesel. Factory tank does have the harpoon and hutch. Done over 650 with the tt.

I travel long distances to places where fuel is significantly more money. Filling both tanks means i can make it there and back with the tt. Save lots of bucks (think a dollar+ per gal). Its worth filling up close to home sometimes.

Heck, not having to stop at a gas station over a long weekend almost makes it worth it alone, especially with the tt. Being able to fill up before the stations jack up their rates for a long weekend can save bucks.

Also not alot of gas stations out in the bush. I frequent those kind of places. You want lots of fuel for the bush. 4low (and in the conditions to which you use 4low) uses a surprisingly high amount of fuel, especially when pulling up a mountain trail. There is nothing but mountains and forests where i am, so its not hard to be hundreds of miles from a gas station.

There was actually 1 time the factory tank vent got clogged (dont ask....) with mud and i couldnt fill it. You had to fill it rreeeaaallll slow. The second tank filled just fine. Victory.

I love the second tank on my ex and works well, but i live in a place that can uniquely take advantage of it.

 

I took measurements under mine with the intention of fabbing an aux tank. It's been a while, but I think it worked out to another 40gal or so.
The plan was to fabricoble a larger fuel door and place both fill ports in the same spot, kinda like the new trucks with the dpf cap.
Personally, I can't understand not wanting more capacity, but to each their own. I mean, who decided fuel capacity had to determine how frequently I choose to stop for reasons other than fuel?

 

If you are towing a camper or heavy trailer, I can definitely see the need for more fuel capacity or a reserve tank. Or even the guys that live in remote areas and it's 50-100 miles to a good station. While I don't have an excursion, I could add an aux tank in place of my useless spare stock spare tire as I currently run 35's, which won't fit afaik

 

I totally agree with the idea of additional fuel to take advantage of fuel prices, especially when traveling but even here at home in SE PA it just makes sense.
At the local station here diesel is currently $3.939 per gallon (PA has the 2nd highest diesel fuel taxes at $.741 per gallon, behind CA’s $.9212 per gallon). Now that I drive a diesel I use either the Open Roads or Mudflap diesel fuel discount programs, the nearest participating truck stop here in PA is 21 miles away and has a pump price of $3.969 and a discount price of $3.354, 25 miles away there is a truck stop in DE with a pump price of $3.759 and a discount price of $2.92. So the difference between local station and the Open Roads discount price 25 miles away is $1.019 per gallon, a 38 gallon fill up saves $38.72 which can buy 13.26 gallons of that cheaper fuel. On a trip it can save a good deal of money when traveling between higher cost fuel and lower prices. I’m looking to add a 72 gallon aux tank in the bed of my F-450 that gets about 9.7 MPG towing our 19K lbs fifth wheel, that will give me 120 gallons onboard or 1100 miles plus of towing range, way beyond my bladder’s range.