cbrahs

I am looking at getting or building an aux tank. The question I have is, does the fuel level system on these trucks set check engine lights when the sensor is not reading any movement? For example, on my 06 dmax (which is sold), it would set a CEL if the PCM did not see any movement (level decreasing). It would set a code for the sending unit. So I added a switching vavle that would also change the senidng unit to the one in the aux tank. The downfall was that the vavle would cut down the size in fuel line (from 1/2 to 3/8 and back to 1/2). I added a sender to the tank but with the valve squeezing the line size down, it would act like it was starving for fuel. I am looking at tapping the aux tank right into the main tank to gravity feed. The sending unit will not see any movement until the aux tank is empty and it is working off the main tank. ANyone have any experience with this?

cquestad

no CEL's on a Dodge...

Drain the tank into the OEM vent line...

My brother is at 1200 miles today...and his gauge still says FULL! LOL.

Just use 3/4" line and tee into the OEM vent. No valve needed. Don't open your OEM cap untill your AUX tank is empty.

I have done this for the last 7 years on three truck...nary an issue.

cbrahs

SWEETTTT . Looks like I am going to have to buy some aluminum diamond plate now! Looking at building something around 100 gallon or so. SInce I have stacks, I am going to build around them to take advantage of the space. Do you return the fuel into the stock tank or to the aux tank?

cbrahs

one last thing, what about the roll over valves? what did you do there?

cquestad

Don't need a roll over valve...both caps are one way vented...in only.

If you managed to crash so hard that the tank/line burst...I think you got other issues. Diesel does not really "burn" anyways.

Don't mess with the OEM return line...it flows mor ethan the 0.5 psi that the static head of your AUX tank can produce...it just pushes the fuel in./..plus it takes more to run than is returned!

cbrahs

Thank you sir!