Hi all,
Sorry for any confusion and thanks for the feedback.
AZKen: yes, I'm generally mechanically competent and able to work on the truck myself, planning on getting it back to my house tomorrow. I would say sudden loss of fuel isn't a guess, the truck drives fine then suddenly the engine has all the symptoms of running out of gas, then comes back to life then "runs out of gas" again. The tank is fully topped up and the truck has been driven at 65 without any issues for 5+ miles at a go and the issue started to kick in both times this year going up hill so I'm 95% confident fuel getting to the engine is the issue here.
As for the fuel pump looking, "fine," I removed the fuel pump from the truck last summer and manually worked the pump and it shot gas without fail. I dismantled the fuel pump and checked the diaphragm for wear or damage and it looked brand new (the fuel pump has maybe 2000 miles on it).
As for the fuel sender the guy I bought the truck from a few years back had it in a box of parts he gave me. When I first ran into issues with it and didn't see anything wrong with the fuel pump I pulled the fuel sending unit out of the gas tank and it was falling apart. I hear what you are saying since it is basically just a tube that pulls fuel so my best guess was an air leak in the line or corrosion, looked like it was original to the truck and I don't know how it was stored by previous owners before it came into my possession.
Lizziemeister: This is what I mean by fuel sending unit
https://www.partsgeek.com/hshh47n-gm...QaApxjEALw_wcB
kknotts: thanks, I've been weighing the value of better reliability by retrofitting parts vs keeping the truck original, good to know you've had good experiences with an electronic fuel pump.
My plan is to get the truck back to my house, check the fuel pump for functionality and/or a leak/oil spray then replace the fuel filter. I'll keep folks posted with my luck, or lack therof!
Best,
Jeff