Fuel Guage not working? switching tanks she dies?

[regal]

I had the bed taken off and a new one put on. While it was in limbo with the bed off I noticed the fuel guages were not working.

With the bed being off I visually looked over the tanks wires etc and all seemed ok.

After new bed went on I topped off both tanks (Both were 3/4 full already)

I ran the front tank to 1/4 full, switched tanks over, and she died.

I switched back to the front and eventually restarted.

So no rear tank pick up, and no front or rear registering a level on the fuel guage. Reads empty

Any thoughts anybody?

[mf7lakes]

were the gauges working before you pulled the bed off the truck?

[regal]

Yes they were working, I noticed they were not working when I moved it with bed off a few days after removal. The truck had sat a while, couple of weeks, visually inspected wires lines, all looked ok, thought maybe the floats had stuck from sitting, ran front tank to what i thought was around 1/4 full, switched tanks and she died, switched back and got it going again. Both guages out, only front tank works.

Not sure if both problems are related and just where to start.

[Devdg]

Get a meter and check that the senders are getting power and a ground. also check to see if your selector valve is working correctly. I removed the box of my truck and there was a ground wire I broke behind the front tank when I loosened the bed bolts.

[mf7lakes]

No expert here - but I agree w/Devdg ............. 1) I think that something with tank selector switch/valve might be going on..... 2) both tank quantity senders going bad at once?....... I don't think so.

Something electrical is broken/short to ground/pinched or something..........tank feed/return hoses pinched????

[Devdg]

I crawled undermy truck and it would be hard to check with the box on if you can take it off and you might see what the issue is right away. It would beat taking the fuel tanks out.

[Grendle]

The fuel gauge wiring goes through the plug at the selector switch.

Inspect the plug. It can be done with the bed on, just hard to get to.

[regal]

Thanks everyone for the insight.

[Mitchalvin]

The selector valves run which tank is pulling fuel and also switches the gauge.