2024 Silverado 3500 Cab/Chassis front filler neck delete?

[24_rambler]

Howdy folks,

 

I'm building up a subframe for my '24 cab/chassis dually to install a truck bed camper on. It would be extremely handy to mount a tool box where the front filler neck is.

On my '06 cab/chassis Duramax, the rear tank pumps into the front tank and the front tank has the suction line leading to the engine-mounted filter (no lift pump). In theory on my '06, I could completely eliminate the front filler neck and just pump into the back tank (if I'm willing to wait on the transfer pump).

Is it a similar setup on the '24 gasser? Eliminating that front filler neck would allow me to mount batteries outside my habitat, making it safer and freeing up a LOT of interior space.

 

Thanks!

[newdude]

1 hour ago, 24_rambler said:

Howdy folks,

 

I'm building up a subframe for my '24 cab/chassis dually to install a truck bed camper on. It would be extremely handy to mount a tool box where the front filler neck is.

On my '06 cab/chassis Duramax, the rear tank pumps into the front tank and the front tank has the suction line leading to the engine-mounted filter (no lift pump). In theory on my '06, I could completely eliminate the front filler neck and just pump into the back tank (if I'm willing to wait on the transfer pump).

Is it a similar setup on the '24 gasser? Eliminating that front filler neck would allow me to mount batteries outside my habitat, making it safer and freeing up a LOT of interior space.

 

Thanks!

 

 

Do you have a legit "chassis cab" or did you order a regular truck with a box or as a "box delete"?  

 

So on the silver door tags on the driver's door jamb, there's a spot for the "model" of the vehicle.  If its a chassis cab it should start with "CC31" or "CK31".  If its a "CC20", "CC30" or "CK20" or "CK30", its a regular pickup.  

 

 

Edited June 11 by newdude

[24_rambler]

This is the chassis cab, flat 34" rails, arrived on the lot with the goofy cheap trailer lights bolted straight to the rails. The only tags inside my door frame are one with the VIN and one saying it was manufactured in Flint; my understanding of any further tags is that they are stuck on by the upfitter. Since this has never had a bed installed I don't have one with tire pressure, GVWR, etc.

The receipt has a model code starting with CK31.

 

I could be wrong, but I think they don't even offer dual tanks for a standard bed 3500 DRW? That's not a topic for this thread though.

[newdude]

On 6/11/2024 at 6:00 PM, 24_rambler said:

This is the chassis cab, flat 34" rails, arrived on the lot with the goofy cheap trailer lights bolted straight to the rails. The only tags inside my door frame are one with the VIN and one saying it was manufactured in Flint; my understanding of any further tags is that they are stuck on by the upfitter. Since this has never had a bed installed I don't have one with tire pressure, GVWR, etc.

The receipt has a model code starting with CK31.

 

I could be wrong, but I think they don't even offer dual tanks for a standard bed 3500 DRW? That's not a topic for this thread though.

 

 

Correct, dual tank is true chassis cab only.

 

Reason I ask is GM has stuff in the upfitter site on fuel tank filler positioning.  2020_PU_Box_removal_Rev_05_13_2022.pdf (gmupfitter.com)      Pages 20 and 21.  

 

As far as using one tank to fill both, here is the description and operation on the dual tank setup:

 

Fuel Pump - Secondary { Fuel Transfer Pump } If equipped

 

The fuel transfer pump is located in the auxiliary (rear) fuel tank. The Engine Control Module (ECM) supplies voltage to the Fuel Pump Power Control Module, which applies power to the fuel transfer pump. The Fuel Pump Power Control Module actuates the fuel transfer pump by using pulse-width modulation to control the fuel pump speed according to serial data signals received from the ECM.

 

When the primary (front) fuel tank level is less than 57 Liters (15.1 Gallons) and the auxiliary fuel tank level is greater than 7 Liters (1.8 Gallons), the fuel transfer pump is commanded On and continues to transfer fuel to the primary fuel tank until the primary fuel tank level reaches 77 Liters (20.3 Gallons) and then the fuel transfer pump is commanded Off.

 

When the auxiliary fuel tank level drops below 7 Liters (1.8 Gallons) and the primary fuel tank is below 77 Liters (20.3 Gallons), the ECM commands the fuel transfer pump on for 84 s to pump the remaining fuel to the primary fuel tank.

To convert Fuel Level Sensor voltages to Liters or Gallons, refer to Fuel System Specifications

 

 

 

Being the primary tank is 25 gallons, and the ECM stops filling the primary from the secondary at 20 gallons, you'd not be able to 100% fill the primary on a fuel fill, if that mattered to you unless you plumbed both fuel fillers and fill both tanks that way.