Hey folks my 85 originally had dual tanks but the PO took the side tank and well the tank behind the axel I kno is a 19 gallon tank and my gauge will say E so ill go fill it up and it usually stops at 20 bux and my gauge is at F how is this possible when gas is 3.50+

 

I learned long ago with this truck to watch the miles. I use the trip odometer and reset it every time I fill up. You should get over 200 miles.

If you have a multimeter, you can measure the sender output.
The reading should be ~10 ohms full and ~73 Ohms empty.
If the sender is reading much higher up to infinity that means the sender wiper is not making proper contact with the resistance wire. In this case the gauge will 'peg' E. Sender parts could be gunked over or bent up or just worn out.
You can measure this at the dash switch. Let me know if you want to try that and I will give more details.

Other possibilities could be the float is saturated, bad connections at tank connector, or maybe even the wrong sender. The PO could have swapped the senders from the front tank just to get something working. The senders are not the same.

 

hey don't complain LOL that's great news. did the truck come with duel gauges? if not it might think the other tank is full all the time.

 

Well here the gas pumps will shut off when the tanks full and it will shut off at or around 20 I'm not complaining its just how does maybe 4 gallons completely fill a 19 gallon tank I don't get it
A buddy if mine took his bed off and looked in his tank I think im gonna try that

 

Maybe my float is messed up because my needle will randomly move around the gauge when its at E if it idles after I fill it the needle will drop here and there and go back up

 

Try going at half speed. When i fill my truck i have to go half speed because the filler tube has to sharp a curve and the gas gets held back and shuts the pump off.

 

I don't think the system was designed for the modern fast fill pumps. I have always had trouble filling without stopping and restarting sometimes several times. Especially if the pump hose has the vapor recovery shroud (CA). If I wanted a fast fill, I sometimes would hold the shroud back with my hand during the entire fill and not put the nozzle all the way into the filler tube.

I live in OR now and am not allowed to pump my own gas. I have to tell the attendant how many gallons I expect to be getting so they can restart the pump when it shuts off. They are not allowed to top off so I will go home and put in 4 or 5 more gallons from a gas can if I plan on going on a long trip.

Unless you have another reason to remove the bed, I think it would be much easier to drop the tank.

 

I'll try droping the tank u ever really considered that thanks for the help guys

 

Just pulled my bed today. If you have access to a lift of any kind this is the way to go. So much easier than disconnecring all the lines and pulling all the bolts out.6 bolts and 2 wiring clips and its off. Literally. That easy. Air tools help. I replaced both pumps today, and then i undercoated everything i could with black paint on top. Including the back of the cab. Took me and my dad about 4 hours total work, with a break inbetween to let it dry a bit.

 

Well I decided I'm gonna paint my truck so I am gonna pull my bed off here in a couple weeks to get it panted plus to cover a few rust spots