Hauling Gas In Transfer Tank (Gas and Diesel Transfer Tanks)

Having an extra tank of fuel on board is one way to make sure you do not run out of gas in the middle of nowhere. However, getting one for gas may be a bit difficult as most transfer tanks are made for diesel fuel. Some research in your area will be needed to find out for sure.

One reason you may not find that many transfer tanks for gasoline is that it is a very volatile fuel. Plus, gasoline is very thin thus it could leak very easily on you or explode under the right circumstances. This may not be a good idea for gas-powered engines.

To learn more about this topic, just continue to read our article. It has the information you need to know before you install any of these tanks in your tow vehicle or RV. Each state may have different regulations on this topic.

Can You Put Gas in a Slip Tank?


Only if the tank is rated and made for gasoline. No other type of tank will do because of the nature of the tank. For example, the slip tank may have to have double walls to protect the fuel from outside influences.

Plus, the slip tank should not be gravity fed. There may be a DOT law governing this transfer mechanism. Also, you cannot use an old diesel slip tank as it is not rated for gasoline.

If you use a tank that is not certified for gas, then if caught, you could face a stiff fine for the violation. There are companies that do make slip tanks for gas but they are few and far in between.

The tanks made by these companies have to meet strict regulations before they are allowed to sell them to the public. Most are used for construction and similar heavy-duty industries.

The key will be to make sure they are certified for gas. Buying used tanks may not be that easy as some owners may say they are certified when they are not. You have to be very careful when buying used tanks.

Can You Haul Gasoline in a Transfer Tank?

Yes, you can and there is one aluminum comp[any that makes these tanks under a special permit from the DOT. There are about 10 rules to follow if you install one of these tanks.

We will give you a link and a few of the rules shortly. First, there are other companies that make these tanks but we have only come across two names so far. Transfer Flow is one, TidyTanks is another but they are Canadian and this one which is A.T.T.A. Some of the rules are:

1. ATTA, Inc. Special Permit #20416 is valid for use with Diesel, Ethanol, Gasoline, Kerosene, Methanol, and Aviation Fuel. The end user is responsible to read ATTA, Inc. Special Permit #20416 before use.

2. Warranty card must be returned to ATTA, Inc. within 30 Days of purchase. Failure to return warranty card will void warranty.

3. Special Permit is valid for 2.5 years from date of manufacturing.

4. Refueling tanks must be retested every 2.5 years in accordance with 49 CFR 180.352. The end user is responsible to keep refueling tank within 49 CFR 180.352 regulations.

5. In order to maintain ATTA, Inc. manufacture warranty for refueling tanks, the refueling tank must be maintained within accordance of 49 CFR 180.352 at all times. Failure to have refueling tank retested every 2.5 years will void warranty. ATTA, Inc. must receive documentation of retesting within the 2.5 years limit to maintain ATTA, Inc. manufacture warranty. Failure to send ATTA, Inc. retesting documentation within the 2.5 year limit will void ATTA, Inc. manufacture warranty.

You can read the rest of the rules at this link and get more information from that company. These tanks are rated for all types of fuel including gas.

Can You Put Gasoline in a Diesel Transfer Tank?


While people may have done this over the years, it is not recommended you do so. The reason is that diesel transfer tanks are not rated to hold gasoline. If you are caught, you could be subject to some heavy fines.

This can pose a problem for many owners as the majority of transfer tanks are rated for diesel only. One reason you can’t do this besides maybe being against the law, is the classification of diesel and gas.

Diesel fuel is classified as a flammable while gas is classified as a combustible and there is a very large difference between the two classifications. All it takes to ignite the latter is a spark.

Whereas you can put a lighted match into diesel and the only thing that will happen is that the match will go out. Gas is far more dangerous than diesel and the tanks are made a bit differently as well.

Diesel fuel is a thicker fuel than gas which means that it won’t normally escape through tiny cracks or holes like gas can. Those leaks can cause a lot of damage if the leaking gas is ignited by some spark or other activity

Difference Between Gas And Diesel Transfer Tanks

The first difference is that the gas transfer tank is usually smaller and lighter than the diesel model. This means that the diesel tank can hold more fuel than the gas one but that difference may be negligible if you get great gas mileage.

Also, diesel tanks are said to be more durable than gasoline tanks. It is a heavier fuel so that difference makes sense. Also, the gas tank sealers are made in such a way that they resist other fluids and keep them from entering the tank.

Then the diesel tank only has to be rated for a flammable liquid while the gas tank has to be rated for a combustible fuel. Fumes from the gas tank can ignite very easily while diesel fumes are not a danger to anyone in most situations.

Since you are carrying less gas because it is smaller, the gas transfer tanks are cheaper than the diesel ones. The price of fuel fluctuates so you may save buying gas or you may save buying diesel depending on their individual prices.

What Makes a Fuel Transfer Tank DOT Approved?


It must be built according to the governing DOT regulations before it can be DOT approved. This is the same with propane tanks. If it does not say DOT approved, then the tank may not have met all those regulations.

Here is the best explanation for this topic:

DOT-rated containers are used in a wide variety of industries. The DOT rating system uses a set of codes to determine if a container possesses the required safety parameters to be used in transportation. The DOT uses a rating system to prevent a container from spilling its contaminants or causing fire or explosion. The DOT-rated containers are often required for certain contents that pose a higher than average risk during transportation.

Many of the DOT standards focus on preventing a container from cracking or rupturing in an accident. This means that a DOT-rated container is specifically designed to sustain higher forces, including vibrations or impacts, as well as extreme temperatures or pressures.” (taken from this website https://sharpsvillecontainer.com/what-is-a-dot-approved-container/ )

To get the specifics on those DOT codes and rating systems, you need to look up the DOT’s website and search it. Or you can contact your DOT office near you and ask where you can find those codes and rating systems that apply to transfer tanks.

These codes can change without notice so it is best to go to the source for accurate information.

DOT Regulations For Fuel Transfer Tanks

We have given you 5 of the rules that apply to this issue. Here are the other 5 rules that you must follow if you are going to install and use a transfer tank on your vehicle or vehicles:

6. Refueling tanks must be attended at all times by a qualified person within accordance of 49 CFR 177.834. Do not leave refueling tank unattended.

7. No modification of refueling tanks is allowed. Do not weld on any fuel tank. Failure will void warranty.

8. Always use proper venting techniques with all fuel tanks.

9. All fuel tanks must be installed per instructions with no exceptions. Transfer pumps must be installed per manufacture requirements.

10. Vehicle with refueling tank installed must be turned off when transferring fuel. Any vehicle or equipment of which fuel is being transferred to must be turned off. Do not transfer fuel near any heat source or open flame. Only transfer fuel in well ventilated areas.

One more rule that may not be mentioned in those 5 or the 5 up above is:

Refueling tanks are designed to be mounted near the head gate in a pickup box, flatbed, or utility box (no other location on the pickup or truck is recommended) (taken from this website- https://www.transferflow.com/regulations )

Also, there may be a limit on how much gas or diesel you can carry in those transfer tanks. We have seen owners mention different limits so that restrictions may be different in all states.

Can You Use a Transfer Tank as a Fuel Tank?


We have not seen any regulation that states that they can be used as fuel tanks. Usually, the transfer tank’s contents have to be pumped out into your regular gas tank. They are not connected or directed to your primary fuel line.

This is the difference between a transfer tank and an auxiliary tank. The latter is plumbed directly into your fuel line and can be used as a fuel tank when the first tank runs out of fuel.

You just have to be quick to move the switch from one tank to the other before your car runs out of gas. Some people say that the auxiliary tank is plumbed directly into your stock factory tank and it refuels that tank when you flip the switch.

An electric fuel pump is often used between the two tanks to get the fuel from one to the other. The things you need to worry about with an auxiliary tank are making sure to shut the pump off and make sure the shut-off valve is put back in place when you do not need it.

The pump used for the transfer tank usually is a manual one operated by a hand crank or pump handle. You have to connect the transfer pump to your factory gas tank and then pump the extra gas into that.

Can You Put Gas in an Aluminum Transfer Tank?

From our research, that metal is about the only one you can use for this purpose. Coming from the Transfer Flow website is this regulation:

Tanks are “Designed using, as a minimum, high-yield 14-gauge aluminized ReliaSteel” We have seen other websites that make transfer tanks and they only sell them using diamond plate aluminum.

There are other regulations that may or may not be DOT originated. One is that the gravity pull system is not to be used with transfer tanks. Also, another requirement is that these tanks must be dropped from 30 feet in the air to make sure they won’t break, crack or lose their seal.

Transfer tanks are a heavily regulated product. The reason for those many regulations is that the government is determined that these tanks be almost 100% safe before they can be used.

Before you go and install; any tank in your vehicle, you should do your own research to make sure that you know all the rules. If any law enforcement agency enforcing those regulations happen to catch you in violation, you may be subject to some harsh disciplinary action.

Don’t let any installer violate those rules either. You will pay for their errors and that is never any fun.

How Much Gasoline Can You Haul?


It seems that the cut-off point for hauling diesel is 119 gallons or 450 liters. For gas, it is 30 liters or 8 gallons maximum. That is according to this DOT statute:

§392.51 Reserve fuel; materials of trade.

Small amounts of fuel for the operation or maintenance of a commercial motor vehicle (including its auxiliary equipment) may be designated as materials of trade (see 49 CFR 171.8).

(a) The aggregate gross weight of all materials of trade on a motor vehicle may not exceed 200 kg (440 pounds).

(b) Packaging for gasoline must be made of metal or plastic and conform to requirements of 49 CFR Parts 171, 172, 173, and 178 or requirements of the Occupational Safety and Health Administration contained in 29 CFR 1910.106.

(c) For Packing Group II (including gasoline), Packing Group III (including aviation fuel and fuel oil), or ORM-D, the material is limited to 30 kg (66 pounds) or 30 L (8 gallons).

(d) For diesel fuel, the capacity of the package is limited to 450 L (119 gallons).

(e) A Division 2.1 material in a cylinder is limited to a gross weight of 100 kg (220 pounds). (A Division 2.1 material is a flammable gas, including liquefied petroleum gas, butane, propane, liquefied natural gas, and methane).”

You can read it at this link.

We cannot say this often enough, check with the authorities first before you buy a transfer tank or have one installed. There are a lot of regulations governing this product and its use.

The Problem With The Gravity Feed Fuel System

The biggest reason you are not supposed to use this type of system is that it can negatively affect your diagnostic systems. Those systems are the ones that are federally mandated and manufacturer implemented on-board vehicle diagnostic systems.

The gravity feed system also keeps your fuel tank over full and can set off error codes. The check engine light may not turn off and you can miss out on legitimate engine issues because of his technicality.

Some owners tend to seal off the rollover valve which stops the fuel from flowing out of the tank in the event of a rollover. The fuel keeps coming out making a bad situation much worse.

If you do seal off this valve you will be in violation of 49 CFR 393.67(12) (i) and (ii) and is also a violation of the 1990 Clean Air Act. As you can see, there are a lot of regulations you need to be aware of when you have a transfer tank installed on your vehicle.

Some Final Words

It is okay to have a transfer tank installed in your vehicle. They come in handy when you are going down some very remote roads and a gas station is 100 miles away or more.

The key to having one in your vehicle is to make sure those tanks meet all the regulations governing their use. If you don’t your costs are going to go up significantly through some heavy fines.

Leave a Comment: