My daughter, my favorite daughter, went and bought herself a new 1995 F150! 4.9L six, auto, 2WD. Only 122,000 miles. It has the dual fuel tanks. We have no idea if the switching process works or not. We see if the dash switch is pushed that the fuel level gage changes position. However, we know the front tank is full, but it only shows 1/3rd full. We know the rear tank is full, and the gage shows full when switched. I have been told that there are two low pressure pumps in the tanks, a high pressure pump, and a vacuum operated switching system. I'll be reading up on my AllData mechanics website soon, to get the official info. But, if you all have any practical advice for my daughter who will be heading back to school for her senior year, that would be great. Do we run on one tank the we know works? Do we run on the trip odometer since the fuel gage appears to be inaccurate?

She's a great kid, who could have been an engineer, but decided to go into psychology. I'm looking forward to free counseling some day.

I have an F-250 with a short bed and dual tanks. Think my front tank holds around 16 and the rear around 17 gallons. I'd set the trip odometer every time I filled up, and use both tanks. Run the tank with the bad gauge first, so she has a reserve of fuel in the tank that has an accurate gauge. I'd guess the front tank would hold fuel sufficient for at least 150 miles. And I'd advise her to fix the thing as soon as she can.

I've used/driven the F150 with dual tanks in the past. When you switch the switch on the tank the gauge should read for that tank.

We had an older one at work once where one of the tanks/pumps stopped working. We just ran it on one tank for awhile.

I would run the tank that doesn't show right on the gauge first then switch to the other tank. You could also do mileage. I've run one tank down to nothing and you will feel the truck hesitate. If that happens just switch tanks(as long as the other tank has gas in it).

Nice truck! I have a 95 F150 shorted 5.0 with dual tanks. The fuel gauge switches to the sending unit for the tank I'm use. I'd a year that you have a faulty sending unit in that tank. How is the body and everything else on the truck?

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I have been told that there are two low pressure pumps in the tanks, a high pressure pump, and a vacuum operated switching system.

On a '95 there is a single high pressure pump/sending unit in each tank and the dash switch shunts power to one or the other. The pump in the bad tank either isn't getting power/ground or is bad.

Try adding Chevron Techron Concentrate to the tank that is getting wrong reading. It will clean up the deposits on the sending unit along with the injectors. Follow directions on how much to mix. A co worker had a late 90s truck that the gas gauge did not work for years. I told him about this, halfway thru 2nd bottle his gas gauge stated working right. He thank me about 1/2 dozen times was so glade it worked.

Not sure if this will help or not, but, a lot of the Fords with dual tanks from that era suffered from a faulty "fuel selector valve." I just replaced mine in my 88 Ford. It is a small type of tank, mounted on the frame rail under the driver's seat, and has 4 lines going in (2 for each tank), and two coming out to the engine.

In my case, the gauges were reading correctly, but, the valve was stuck in the middle, and this allowed gas to flow from my rear tank to my front. Sometimes you would see gas coming out of the filler . Made the truck run like hell also (too rich?).

Good luck, and hope that helps.

I have a '91 F-150/5.0L/124k miles I've had since new with a front tank gauge that quit working a few years ago. Based on running the tank dry at around 220-230 miles a few times, I now switch to the rear tank that still indicates properly at no greater than 200 miles. I reset the trip odometer at each fill up and switch to the front tank.

As long as the tank selector switch works its really not a big deal to run the front tank out of gas while driving. The truck will gradually lose power but picks up immediately when the tank is switched to the rear. I don't do this regularly since its hard on the fuel pump and has the potential to suck up debris from the tank.

On those year Ford trucks (I still have a '94)If the gauge on one tank only goes up to a certain level even when full, it is most likely that the sending unit connected to the pump is probably bad or stuck. As the sending unit is integrated to the electric Fuel Pump (one in each tank), the pump has to be changed out if you can't get it "unstuck" using some gas cleaner in the suspect tank.

The worse problem is that if the pump is old enough to have the sending unit stuck/bad there is also a good chance the internal valves of the pump are also suspect, which is shown when running one tank affects the amount of fuel in the other tank, since they are directly connected to each other. As someone mentioned, this can even cause the backflow to push gas out the gas fill spout of the tank you are not switched to if it gets too full. It can also cause the truck to run poorly because the engine runs too lean since much of the fuel pressure will be bled to the other tank if it gets too bad.

If running off one tank does not affect the fuel level of the other tank and simply gets stuck at a certain level on the fuel gauge, I would try a full front tank with a bunch of gas cleaner first and try to get the float/arm unstuck.

If either tank shows any signs of previous or current spillage out the fuel spout (my truck has the paint under the fuel spouts faded), it is likely the fuel back flow valves are also bad. Of the two, the most likely culprit is the front tank fuel pump.

Prior to 1994, it could also be the tank selector, but since yours is 1995 it's most likely the front tank fuel pump. It's easy to simply drop the front tank (only held on with two strap bolts) and swap out the fuel pump.

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1995 F150 Dual Fuel Tank Advice Requested

My 91 had the fuel return problem as well. As you drove on one tank the other would start filling up so you had to switch tanks all the time and could never fill up completely... not that I could afford two tanks of fuel back then anyway.

When the pump in the front tank went bad and I couldn't use it that tank would sometimes overflow. I'd switch tanks and limp along on the bad pump for a while, usually on the freeway where I didn't have to accelerate, until I'd burned off some of that gas. I ended up getting a siphon set and siphoning gas from one tank to the other every few days.

The problem with that era of truck is the pumps being in the tank, on top of the tank, so you either have to pull the bed or drop the tank to get to it.

Once I got it all fixed the truck ran great and served me well for another 10 years. The 4.9 I6 is bulletproof.

our "94" ford truck did the same thing.
a ford dealer mechanic told us that the system went bad because we had run the tank dry too often , before switching to the full tank.

these systems were not designed to be run totally dry , before switching to the other ( full ) tank