7" Instrument Cluster Upgrade with 50 Gallon Fuel Tank

[01Time]

I was able to get my hands on a 7" cluster to upgrade to, but I don't think it's accurately displaying my fuel status. I have a factory 50 gallon tank that read fine before I swapped clusters. Now, the fuel gauge seems to behave more like it has a 32 gallon tank. At about a 1/4 tank it only takes 20-25 gallons to fill up (gauge reads full and pump auto-stops). The only changes I made with AlfaOBD were the odometer correction...here's what is showing in the BCM settings that may be relevant:

VehConfig 3:
   Fuel Capacity (36-290 L): 189.000 Liters
Cluster:
   Fuel Tank 1 Calibration, Full Datum for Fuel Voltage 1: 0
   Fuel Tank 1 Calibration, 3/4 datum for Fuel Voltage 1: 0.000
   Fuel Tank 1 Calibration, 1/2 datum for Fuel Voltage 1: 0.000
   Fuel Tank 1 Calibration, 1/4 datum for Fuel Voltage 1: 0.000
   Fuel Tank 1 Calibration, LFW datum for Fuel Voltage 1: 0.000
   Fuel Tank 1 Calibration, Empty datum for Fuel Voltage 1: 0.000
   Fuel Tank 1 Calibration, E Stop Datum for Fuel Voltage 1: 0
   Fuel Tank 1 Calibration, Empty:  2%
   Fuel Tank 1 Calibration, LFW:  8%

It's been several weeks. Any ideas?

 

[Brutal_HO]

Those settings match my 50 gal factory Limited.

??

Dare I say, have you tried to run it down to the fuel low light?

 

[01Time]

Those settings match my 50 gal factory Limited.

??

Dare I say, have you tried to run it down to the fuel low light?

I don't normally run it down too much past half; especially with fuel prices like they are now. As a matter of fact, where I normally refuel, the pump stops at $125.

The DTE and gauge seem so erratic. A full tank shows close to 800 miles DTE (which is consistent with 50 gallons). But then I'll drive just 50-60 miles and the DTE is at 500 and I'm at 3/4 tank. Just doesn't make sense.

Maybe I should just write down my milage and how much fuel I pump and figure out my mpg the old school way to be sure.

 

[Millmutt]

I have a 20 Laramie CC LB with the 50 gallon. The gauge seems to go down in a pretty linear fashion. I fill up completely and run it down pretty low each tank maybe 20 miles to empty. I have put in 48.5 several times.

 

[01Time]

I'm not ruling out operator error...I'll run it down to E and then fill up...