Auxiliary fuel tank

TTTONY · August 10, 2020

I'm wanting to put in auxiliary tank on my 2020 1 ton hd Duramax is there any problems with a standard set up or is there something special I need to keep the computer from throwing a code

rblanch · August 10, 2020

I just installed one however I haven't tried it out yet can let you know towards the end of the week

rforten · August 11, 2020

I have a 60 gallon auxiliary tank on mine. If I leave the aux tank open to gravity feed into the main truck tank, it throws a CEL after awhile. The Code Reader describes it as a problem with the fuel level sensor.

Apparently, if the gas gage doesn't go down while you're driving it throws an error.

The good news is that the CEL goes away once the Aux is empty and the main tank starts going down on its own.

Kind of a worthless error to look for if you ask me.

rblanch · August 25, 2020

I installed mine with a small fuel pump I turn on from the upfitter switch. So far no problems.

Madams1970 · July 18, 2023

On 8/11/2020 at 4:11 PM, rforten said:

I have a 60 gallon auxiliary tank on mine. If I leave the aux tank open to gravity feed into the main truck tank, it throws a CEL after awhile. The Code Reader describes it as a problem with the fuel level sensor.

Apparently, if the gas gage doesn't go down while you're driving it throws an error.

The good news is that the CEL goes away once the Aux is empty and the main tank starts going down on its own.

Kind of a worthless error to look for if you ask me.

I am having same issues, after driving about 100 miles fuel gauge goes to empty. this is a problem.. pull the negative batt cables and resets computer.

Lizard Power · October 3, 2023

I was looking into this Titan fuel tank. Seems everything stays standard. https://titanfueltanks.com/products/xxl-replacement-tanks?find=2020-chevy---gmc-2500-4839&sid=IZ0goVJdJJ.

1fast ss · October 3, 2023

I have a 60 gallon tank and have experienced the CEL and the gas gauge dropping to empty. What I currently do is once I get to half a tank I open the valve. It allows for the fuel leveler sensor to still move and still gives an estimated mileage range as well. No CEL's or empty tank reading since doing it that way.