How Do Ford Dual Fuel Tanks Work

Ford dual fuel tanks can pose a lot of questions, like how they even work at all. It can feel strange, and this is a question you want to be answered. Let us look at how the twin fuel tanks of Ford heavy-duty trucks work.

How Ford Dual Fuel Tanks Work

The twin fuel tanks in the Ford truck are known as the primary and the secondary fuel tank. The primary fuel tank performs the function of channeling fuel directly to your truck’s engine while the secondary tank takes in fuel, but this depends on the fuel available in the primary tank.

What happens is that these two components work at the same time. A single pipe connects the two tanks, making them function the way they do. While driving, what happens is that the primary tank transports water to the engine through the discharge channel. The secondary tank then changes the energy used by the primary tank.

Once you turn on your truck’s engine, the fuel pump does its job. This procedure keeps going, except the acceleration speed reduces to 120 ppm, or you turn off the engine of your Ford Truck. When you turn off your vehicle’s engine, a control module stops the operation of the fuel at once.

The Twin Fuel Tank Design

The design of this tank is fashioned in two different patterns. The series and the parallel. The function of the series fashion is to make sure that fuel flows naturally, directly into the car’s engine, while the parallel performs the function by using two different fuel pipes that meet at a junction.

This design system has some components that it works with to perform its functions. Let’s take a look at some of these components.


These fuel reservoirs can come in handy for you when needed. They act as a storage medium like when you are low on fuel, and these reservoirs can help channel fuel to your truck’s engine.

Screen and Filter

These screens and filters help to make sure that there is proper pressure regulation in the car’s system. The screens, or sometimes the filters, consisting of four individual parts which perform the function of regulating the truck’s fuel pressure.

Shuttle Regulator Valves

This performs the function of regulating fuel pressure. It reduces the fuel amount in the diaphragm by opening its return line.

Supply Check Valve

This component works when you turn off your car’s engine. This is done by the supply check by shutting its outlet to maintain the fuel pressure and keep the pump line in check.

Venturi Jetvalve

The system sends the fuel to the tank through the jet valve whenever there is excess pressure from the fuel pump. It ensures that the engine continues getting fuel, especially when the primary tank is low on fuel.

Pressure Regulator

This regulator is a necessary component for the twin fuel tank to work. The function it performs is simple. What it does is that it makes sure that there is a continuous fuel pressure in the diaphragm through a balanced pressure. The diaphragm has a spring that the regulator uses to ensure this continuous fuel pressure.

Problems Involved with the Dual Fuel Tank

The dual-fuel tank sounds awesome enough, yet it has flaws. These flaws are generally known to be two. These are fuel cranking in the engine and the transfer of fuel. These problems can even happen when the truck’s engine is not running. The overload tank and the tank selector are other problems associated with the double fuel tank.

A Solution to the Problems

It’s good that the problems associated with the dual fuel tank can be solved even through a DIY procedure. One of the solutions is using the recall tool produced by Ford. This tool is used to stop the two major problems that affect the twin fuel tank. The tool has valves with one fuel pressure controller that does not allow fuel flow through the supply pipe.

Even though it might not be a total solution to the problem, it will go a long way in stopping this cranking of fuel in the engine for a long time. If the pumps have a problem, you could use this tool to push enough pressure to Ford’s return tank.

This recall kit can go a long way for your dual fuel tank problems.

What is the Sign that You Should Change My Fuel Pump?

Before your fuel pump gives out, there are some ways that you will know that it needs to be replaced before it gives in totally. Some of these are:


Fuel pumps should normally give a low sound, so when your fuel pump begins to cause noise pollution, it’s a sign that you need to replace it.

Ignition problem

A big sign that your Ford’s fuel pump may have a fault is that it starts to drag when trying to start the engine. This means that there is no proper flow of fuel into the engine. This could be a problem with the pump, so you should take it to a repair shop.

The engine becomes unstable.

You will notice that while driving, it will look like your car is about to go off. While driving, it may be jerking forward at sudden intervals. This means that there is not a proper flow of fuel from the pump to your car’s engine.

Fuel Consumption

This happens because excess fuel may pump into the car’s engine. Especially during acceleration, your engine will drag more fuel when the pump is bad.

Turning Off of the Car

Your car can suddenly turn off when there is an insufficient supply of fuel to the engine, especially when you approach a hill. The car can turn off because the pump does not work well again.


The introduction of the double fuel tank is a brilliant production. They are best if you’re someone who drives on a rough road. They are also great if you are a traveler. The secondary tank can serve as a storage medium.

Liam Dare

As CEO of, my passion for the automotive world motivates me to build online businesses that provide information and entertainment to users. I am proud to contribute in a positive way to the automotive community.