DIY aux tank for truck

[handirifle]

I have been reading about some folks that have made their own aux diesel fuel tanks for mounting UNDER the truck bed, and plumbed into the system to fill and drin as the main tank does, no switch over system. Anyone here done this?

 

[Diamondpilot]

There are companies that simply make larger oem style tanks. They are usually 50% or more larger. To me this would be the best option.

Chris

 

[handirifle]

Replacement tanks cost more than I can afford, at $1200-1500. Too much money in my home.

 

[aeblank]

Check out some truck forums. dieselplace.com, duramaxforum.com, gm-trucks.com, duramaxdiesels.com.
Can you tell what kind of truck *I* have?

Anyway, all sorts of fuel tank mods. I know I saw a thread on one of them of someone doing what you are suggesting. They had two lines on it, one on the bottom and then they tied a vent in to the existing vent. I'd love a 50+ gallon tank too, but they are *insane* expensive.

 

[handirifle]

On the Duramaxforum, there is one guy that added a 20 gal in front of factory tank but his is a long bed, mine is short. I have to look under mine to see if there is room in front of the stocker. I'll have to check the others.

 

[aeblank]

Makes sense. That must have been the one I was thinking about. My bladder isn't big enough to support a larger tank. Ha-ha.

 

[handirifle]

I can go about 30 gallons worth, when towing (12 MPG) but no way if empty. I have looked and the 36 gal from the newer models, I have a cross member in the way so that idea is out.

I looked under my truck and really don't see a decent spot in front of factory tank to put one. I might end up with something like the Titan Sidekick. It's a 15 gallon tank that goes in the wheel well. It's not designed to be a direct connection tank though, no DOT approval on it. If I have to stop and pump fuel, I'd probably stop at a station. That kinda defeats the purpose of extra fuel, to me.

 

[aeblank]

Nobody would ever notice a small hose with a solenoid valve diving into the truck. Wink wink, nod nod. What size is your tank? I have a lml with 36gal tank. 600 Mile range when empty and cruising at 63mph....

 

[handirifle]

My tank is a 20/26 gallon tank. The absolute most I have put in it has been 21 gallons and I had been driving on empty. NOT something I want to do.

Titan sells a kit like you describe. I have not ruled it out.

 

[ultrarunner]

When I worked in a Fab shop the welder was always building custom Motorhome tanks... it was a lost easier in the days before fuel injection.

He made them from Stainless with baffles and custom to fit the space available.

I would imagine the liability would scare a lot of fabricators today.

I have seen in bed tanks with transfer pumps that were switch controlled.

My old Chevrolet work van has a factory 36 gallon tank which I find to be very practical...

If I can find the info I will post it about someone adapting a boat aux tank.