2010 Western star

The fuel sender connects to the RX module which converts the analog signal to digital and sends that on the PI bus to the star gauges. If a fuel sender didn't fix the issue then I'd be going to the RX module as the next likely culprit (most likely really). Here's a link to a site that has a picture of where it's located on your truck.

http://www.dtnaecomponents.com/West...900EPA2010FrontWallLeftHandSideLookingAft.htm

At the bottom of that page there's 2 connectors that if you hover your mouse over them will say RX_MOD_2A and RX_MOD_1A. That's where the rx module is.

If you disconnect the 16 pin connector on the RX module and test for resistance between pins G and pin H. There should be between 260 and 20 ohms depending on your fuel level. If you see that then the wiring to the fuel sender and the sender itself are fine. That leaves the issue being the RX module or something farther up the line. In the shop I'd connect a known good RX module to make sure it is the issue.

It could also be your gauge, they can be faulty. The gauges are all connected in parallel with one cable that comes from the speedometer, the connector that's plugged into the gauge could be faulty so you can try plugging any of the others into it and see if it reads after that, the wire harness for the gauges is less likely to be the issue tho, only seen that once.