So I hop in truck yesterday and fuel gauge wasn’t working,first time in 30 years.It was on full then pegged past full and I knew it had about 1/4.So I made it 6 miles down I-90 and the truck dies.Called a buddy to get towed and he brought fuel just to try.It did start for a short time but we towed to the next exit.We looked it over and had no pressure at schrader valve and no fuel in bowl.So I filled bowl and tried starting and no start.Now I notice the volt gauge showing 8 volts and we hooked up cables from the other f-250 and still showed 8 volts and no start.It seems to be turning over good.It does have 2 tanks but 1 hasn’t been used because of leak so it might the cross over mechanism.Does anyone know if there is something electrical on these fuel systems that can go bad.I do have another truck I can borrow parts off.Thanks for looking.

Plugged up in line filters?

I am not a diesel guy, but 8 volts is going to cause a lot of issues.

If it's got fuel and acting like it's not geting it I would suspect a bad fuel pump. I'm not sure on a 96 but on my 2001 7.3 the pump was on the frame rail. sounds similar as when my pump failed in it.

Both batteries show 13 volts but gauge shows 8.A lot of stuff going on

That's quite a voltage drop somewhere. Ground go bad somewhere?

It has a pump in valley on top of intake that runs off the cam.They are notorious for leaking and I just replaced the one in my other truck.

rings a bell I think the one on my 92 7.3 idi is manual and functions off a lever that runs off the crank. Your post reminded me I changed that maybe 15 years ago but forgot all about it.

The fuel pump is run by oil pressure.

If your batteries are at 13V and your instrument cluster gauge shows 8V, ,along with a fuel gauge going wonky, ou need to address that first. Offhand, it sounds like a ground issue. If it were in my bay, the first thing I'd do is hook up a scan tool and check codes, or to see if the scan tool can even communicate.

Bad ground

Mine did the same thing gauge wise and the ground on the frame rail was beyond corroded

Neighbor has a 1990 that the lift pump went out it was less then 2 years old.this is run off of the cam it would run like crap.took a gas can and put diesel in it unhooked the line from the tank and ran a line from the lift pump into the can when we lifted the can in the air it would run but when it was set on the ground the pump was weak and wouldn't pump it up into the main pump replaced and it purrs like a kitten.

Check your grounds. And always keep a spare crank sensor in the glovebox of a 7.3

Had over 300,000 miles on my last 7.3 and I never replaced the crank sensor. I replaced the fuel pump and the injector harness that serves as the valve cover gasket. If I remember correctly the faulty injector wiring harness made my voltage meter read low, but I may not be recalling correctly.

I have a 1995 that’s only got 260,000 and it’s on crank sensor #3. It only takes a minute to swap, but I got stranded because of it once. It would start and run fine, then randomly shut off

AL mine was a 97. The biggest issue was the weird spring flywheel Ford used. I changed mine to a solid flywheel and heavy duty clutch

Mine has a valair dual disk setup. It’s actually being used as our crummy currently. I’m more partial to Cummins personally, but I got my ‘95 power stroke for $4,500 so I couldn’t pass on it

Rodent damage a possibility?

Would definitely clean the ground connections at battery and frame

Thanks to everyone that posted.I’m towing it to my garage this morning but not sure when I’ll start working on it.