Auxillary tank under the bed for 2008 F350? - Diesel Forum

tonystrong · 09-10-2007, 07:13 PM

I've got a 2008 F350 SB CC 6.4. I guess when they ordered it the optional 30 gallon tank wasn't checked on the form. It only takes 20 gallons when filling it up and that's quite annoying when hauling the race car or the boat.

Does anyone make an under the bed auxillary tank for the 2008 SB? It would be nice to be able to go more than 200 miles before filling up on road trips.

Y2KPSD · 09-10-2007, 11:20 PM

http://www.transferflow.com/Ford_replacement_tank.html

Check these out,
Had one on my 1991 F350

Blackcloud2k · 09-11-2007, 11:07 AM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: tonystrong</div><div class="ubbcode-body">I've got a 2008 F350 SB CC 6.4. I guess when they ordered it the optional 30 gallon tank wasn't checked on the form. It only takes 20 gallons when filling it up and that's quite annoying when hauling the race car or the boat.

Does anyone make an under the bed auxillary tank for the 2008 SB? It would be nice to be able to go more than 200 miles before filling up on road trips. </div></div>

Wow that is a small tank. Are you sure its not a 30 gal? Have you tried filling it all the way up till you see the fuel, and not when the pump shuts off?

**DSTRBD** · 09-11-2007, 11:21 AM

Look at the Titan Tanks. They make a 52 gal. unit. We put one under a 2008 CC SB truck. Fit just like stock and is made from the same material. Here is a link to them.

http://www.supertanks.com/ford.html

ff1809 · 09-11-2007, 08:25 PM

If i remember correctorly, their were two available size fule tanks for the new 250/350. The shortbeds have the 30 gallon tank, and the longbeds have a 38 gallon tank. I think those were the options so dont shoot me if im wrong.
Anyway, several companies make a Aux. tank that fits in the truck bed were a tool box would go. And some of them have a smaller tool box built in. They hook into the exsisting tank so they add to the cappacity of the origanal tank. Just another option to look at, I dont have one myself because I have the low-pro tool box.
Hope this helps ya some. Robbie

ff1809 · 09-11-2007, 09:19 PM

Here is an example of what I was talking about: http://www.northerntool.com/webapp/w...6721_200306721

I think this is a cheaper method and you would have a combined fuel capacity of about 90 gallons.
Again hope this helps. Robbie

SVTKYLE · 09-11-2007, 10:24 PM

there is no way that truck only has a 20 gallon tank

westvandude · 09-12-2007, 12:04 AM

That's really odd. Ford.com F350 specifications show either 30.5 or 38gal fuel tank depending if you got the short or long bed. Can't have a big tank with the short bed. If you only get 20gal in your 2008 truck then I'd suggest you head to the dealer and tell him your fuel sender is broken.

SmokeyWren · 09-12-2007, 07:37 AM

There are several options to increasing your fuel capacity. But be careful of "cheap" fuel tanks. Be certain any fuel tank you add to your pickup is DOT approved. The good stuff is made by TransferFlow, and is not cheap. You can "make do" with lesser brands if you don't mind doing some pumping of the fuel yourself instead of having a fully automagic system tied to your fuel gauge, or with a fuel gauge that doesn't tell you how much fuel you have left.

It sounds like your best bet would be to replace your 30-gallon tank with a bigger one. The 46-gallon replacement tank from that link posted by Y2KPSD above is probably what you need.

Another option is an in-bed auxiliary tank. Several choices there, from 30 to over 100 gallons, including just a tank, or a combo tank/toolbox, or an "L" shaped fuel tank in the front of the bed with a toolbox sitting on the lower part of the tank.

When shopping for fuel tanks, understand the difference between a replacement tank, an auxiliary tank, and a refuel tank. A refuel tank is more common, because it costs a lot less. Refuel tanks are most often used to haul fuel to farm tractors or construction equipment, but they also work fine to haul extra fuel for your pickup. It is simply an extra fuel tank, not tied into your fuel system. If you want to use the fuel in the refuel tank, you have to stop and transfer the fuel, using a pump of some sort.

For a replacement or auxiliary tank, I'd go with TransferFlow. But for a refuel tank, almost any brand will do. The important part of a refuel tank is the pump that would transfer the fuel from the refuel tank to the truck's fuel tank. The really-good 12-volt electric pumps are not cheap, so you wind up paying almost as much total (including the pump) as for a TransferFlow auxiliary tank.

There are no factory optional fuel tanks on a SuperDuty pickup. Your shorty has a 30-gallon fuel tank, and it will actually hold about 32 or 33 gallons when you fill it up to where liquid diesel is visible at the cap. If you get only 20 gallons in your stock tank when the "empty" light is on, then you aren't filling it up. After the automatic pump shuts off, you can then dribble more fuel in through the foam. It takes me 5 to 10 minutes of dribbling to add the extra 5 gallons or so that will go in mine after the automatic shutoff. But some truckstop diesel pumps won't allow you to dribble it in - it's either a bunch or nothing. In that case I usually just delay filling completely up until I find a different pump that will allow me to slowly dribble in the fuel slow enough that the foam melts as fast as the flow makes new foam.

RockRidge · 09-12-2007, 12:38 PM

SmokeyWren: very well stated! I agree with everything you said. I have had both the 30 (in the shortbed) and 38 gal tank (in the longbed) and they both act the same. If you're patient and wait for the foam to go down, you can get a bunch of extra fuel into the tank.

Tonystrong: If you truly can only get 20 gals into your tank, you may have a mechanical problem. It's under warranty...take it back to the dealer and get it checked out. If you are handy with tools you may be able to "harpoon" your tank to get it to fill faster. Just do a search for "harpoon" on this forum for more on this subject.

[edit] try this link for the harpoon mod: http://www.forgotton.net/diesel/intank/index.htm

guardrail22 · 09-12-2007, 07:46 PM

what he said - either 30 or 38.

unless

you bought a CC chassis and not a pickup - which has a tank between rails in back behind axle.

SmokeyWren · 09-13-2007, 09:25 AM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: guardrail22</div><div class="ubbcode-body">what he said - either 30 or 38.

unless

you bought a CC chassis and not a pickup - which has a tank between rails in back behind axle. </div></div>

The OP's truck is a shorty, and they don't make shorty chassis cabs. [img]/forums/images/%%GRAEMLIN_URL%%/smile.gif[/img]

For chassis cabs, a ~40-gallon tank behind the rear axle was standard, but a midships 19-gallon tank was optional. If his truck is a chassis cab with only the 19-gallon fuel tank, then his 20-gallon fill would make sense. Some roll-back wreckers have only the 19-gallon factory tank. They can't go very far between fillups. [img]/forums/images/%%GRAEMLIN_URL%%/crazy.gif[/img] So owners of F-550 roll-back wreckers are good customers of TransferFlow. [img]/forums/images/%%GRAEMLIN_URL%%/smile.gif[/img]

jetskier · 09-13-2007, 05:52 PM

I still can't figure out why they don't offer a larger factory tanks based on your cab configuration AND bed length. It's great Ford finally started offering variable GVWR based on the different cab/bed configs (click the Payload Package Selector). Since they are only getting 8-11 MPG when towing (if you're lucky), it be nice to have the extra capacity from the factory.

Here's what must fit because the aftermarket does it:

RC LB (137" WB) - 38 gallon (standard)
CC SB (158" WB) & SC SB (142" WB)- 46 gallon
CC LB (156" WB) & SC LB (172" WB)- 57 or 60 gallon (new for 2008 TF)

If companies like Transfer Flow and Titan can do it, why can't the factory? Wake up Ford!!!

RockRidge · 09-13-2007, 06:17 PM

I think the simple answer to that question is..... MONEY .... on Fords part. Look at it this way, if the part only cost $5.00 extra per truck, and Ford builds 200,000 a year, that's a direct expense of $1 Million.

Would I like a bigger tank... Sure. Would MOST people (ie. the masses) want a larger tank, I don't know. Look how many of us bought the trucks we have, versus how many of us actually buy the aftermarket tanks. (on a side note, look how many 4 wheel drives there are on the road, and how many are pavement queens; will never see dirt). The aftermarket suppliers do good business; like most things some are very good products and some are junk, but are they selling 200,000 units a year? That tells me that not too many people rank a very large fuel tank high on their "required" list.

I'd like better mileage too, but I didn't buy the truck for it's mileage; I bought it to tow stuff with. Would I be happy with even a 1 or 2 MPG change for the better? Sure... Fuel mileage wasn't real high on my requirement list when I bought this one, It's just the cost of running the vehicle. Like someone else said... When it's empty, I fill it up.

Just my 2¢ worth.

jetskier · 09-13-2007, 06:29 PM

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: RockRidge</div><div class="ubbcode-body">When it's empty, I fill it up.</div></div>

I do the same, but if it came with more I'd surely take it. I'd even pay the extra $5. [img]/forums/images/%%GRAEMLIN_URL%%/smile.gif[/img] At the time I bought my truck new in 2000, 38 gallons seemed like a lot coming from a Ranger with a 17 gallon tank. Now that I tow, more capacity would be a plus. You're right, that is what the aftermarket is for.