Polyethylene vs Metal Gas Tanks

What You Need to Know

At the end of the day, you just want a gas tank that’s tough, dependable and affordable – nothing more, nothing less. Thanks to new innovations in their design, you now have options when it comes to replacing your truck’s gas tank. In the past, most vehicles were outfitted with steel-coated gas tanks that are sturdy and reliable, but quite heavy. With enhanced regulations from the Environmental Protection Agency, automotive manufacturers now have to build vehicles that are more environmentally-friendly, consume gas more efficiently, and have longer useful lives.

As a result, many companies began designing polyethylene fuel tanks. These tanks, which can be 20 percent lighter than steel tanks, have become just as reliable, if not more so, than their steel counterparts.

Of course, you can choose to use OEM replacement parts when fixing your vehicle, but these products usually carry highly inflated price tags. By choosing aftermarket products instead, you can save a considerable amount of money without compromising on the integrity of your vehicle.

As you begin your search for a replacement gas tank, it’s important to consider all of your options and make the most informed choice that makes sense for your specific situation.

Over the course of 30 years, Raybuck Autobody Parts has helped our customers understand all of their options when it comes to restoring or upgrading their vehicles. With that in mind, when you’re looking for an aftermarket gas tank for your truck, rely on our knowledge to help select the right steel or plastic option.

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Not sure which one is right for you? Take a look at the pros and cons.

poly vs metal fuel tank

Polyethylene Gas Tanks



Recent research indicates that 98 percent of all vehicles in Europe are outfitted with plastic gas tanks, and 75 percent of all vehicles in the United States have plastic tanks as well.

Thanks to innovations in technology, many manufacturers are starting to design plastic gas tanks that adhere to EPA regulations while also increasing vehicle efficiency. Durable and affordable, polyethylene gas tanks get the job done. There are other benefits for polyethylene gas tanks that are comparable to metal tanks:


Flexibility – While breakthroughs in steel manufacturing have made the metal more flexible, there’s nothing more flexible than plastic. Plastic gas tanks for Chevy and Ford trucks come in many shapes and sizes, and they can be completely customized to fit into a specific spot. Their versatility is important, since the undercarriage of any vehicle is complex.



Lack of rupturing – Because plastic is a softer material, many manufacturers criticize its safety features. If plastic is exposed to fire, chances are it will melt and cause fuel to leak out, adding to the flames. However, that can sometimes be better than steel tanks exploding in similar circumstances. Plastics can also flatten or bend rather than rupture like their steel counterparts.



Lightweight – In addition to being softer, plastic is also much lighter than steel. While replacement polyethylene gas tanks are made of thick plastic for safety and regulatory reasons, they can weigh as much as 20 percent less, leading to better fuel economy.



Quiet sound – Thanks to the insulating properties of plastics, when you choose a polyethylene gas tank to replace your metal one, you won’t hear gasoline moving around in your fuel tank.



No corrosion – All vehicles succumb to the rigors of the road: salt, gravel and other debris. While these materials contribute to corrosion on metal gas tanks, polyethylene gas tanks aren’t affected. Water can also destroy a metal tank. Water vapors naturally build up on the inside of a tank when it’s not completely full of fuel. These vapors will cause a metal tank to rust from the inside out, whereas they will not affect a plastic tank. Since plastic gas tanks are not susceptible to corrosion, they will ultimately have longer useful lives.

Because of the myriad of features plastic gas tanks afford, manufacturers are increasing their production. As the industry continues to advance, this trend will continue and become even more pronounced.

Metal Gas Tanks

Metal gas tanks may be the right choice for a variety of situations. To determine if they’re a good fit for your application, review the long list of benefits:


Lower price – For decades, automotive manufacturers relied on metal gas tanks to hold the fuel that powers their vehicles. These manufacturers have invested heavily in the infrastructure necessary to produce these tanks. Many of them keep their stamping, welding and assembly equipment in-house, which allows them to produce metal tanks at a lower price per unit compared to plastic ones.


Reliability – Steel tanks are also extremely reliable. They are made to meet permeability requirements. While they may be heavier, they are also a proven piece of equipment, boasting an impressive track record that dates back 100 years.



Safety – Steel can also withstand high temperatures, ensuring your safety in the event excessive heat comes from your malfunctioning muffler or tailpipe. Additionally, in the event of a fire, steel tanks are less likely to succumb than their plastic counterparts, according to the American Iron and Steel Institute.


Environmentally-friendly – EPA regulations charge automobile equipment manufacturers with the task of producing hardware that can be recycled, and steel is easily recyclable. In fact, nearly 11 million tons of automotive steel are recycled each year. After that process, new steel products are made from the salvaged metal.

leakLess Leakage – Metal gas tanks are also great when it comes to ultra-low evaporative emissions. While the EPA legislated the need for closed fuel symptoms in 1971, a small amount of fuel leakage remains in gas tanks. In order to achieve an enviable, environmentally-friendly Partial Zero Emissions Vehicle (PZEV) status, tanks are only allowed to emit 20 milligrams of fuel each day. In 2005, 29 PZEV-certified vehicles had metal gas tanks — steel can better prevent leakage.

Moving Your Replacement Gas Tank Search Forward

As you move forward on your search for the most appropriate aftermarket gas tank for your truck, you should determine the answers to the following questions. This will help you get familiarized with all available options as well as your personal goals.

While a metal gas tank will definitely be the answer in some situations, it may not be the right fit in others.

  • How important is cost? While you might be able to get a metal gas tank for slightly less money than its plastic counterpart, the price difference is negligible over the course of the equipment’s useful life. You also have to consider any hidden costs that you may encounter down the line. For example, your steel tank might corrode quickly after a few particularly gruesome winters forcing you to replace it again.
  • How important are the environmentally-conscious features of your gas tank? Whether you end up choosing a metal tank or a plastic tank, both options have their benefits when it comes to the environment. Steel tanks are more permeable and are less likely to leak excess fuel. They’re also more likely to be PZEV-certified. On the other hand, because they’re made of steel, they are considerably heavier than plastic options. You’ll burn more fuel when you use steel tanks than when you use the plastic counterparts.
  • Are you concerned with the price of gas? Gas prices are high, and there’s no indication that they’ll decrease anytime soon. If you’re concerned about how much you spend on fuel, you should consider getting a plastic gas tank instead of a metal one.
  • What kinds of safety features are you looking for? Similar to their environmental benefits, both metal and polyethylene gas tanks have their own safety features as well. Which safety features are most important to your typical situations? Metal tanks are sturdy and rigid, which means they can take a beating. But that also means they lack the flexibility of plastic tanks, which are able to bend and contort under pressure.
  • Have you heard of delamination? Right now, Ford is facing a lawsuit that alleges the vehicle manufacturer sold trucks it knew had defective gas tanks. The metal gas tanks suffered from delamination, meaning metal would flake off from the internal lining of the fuel tank. That loose metal could clog the truck’s fuel system. The end result? A less powerful engine that might stall from time to time, causing expensive repairs. With polyethylene gas tanks, delamination isn’t a problem.

Choosing the Replacement Gas Tanks That Are Best For You

Whether you choose metal or polyethylene, both gas tank options are very similar when it comes to functionality. Beyond functionality, there’s a whole scope of other factors to consider when buying a replacement gas tank. In order to make the decision that’s right for you, it’s important to weigh your options. If you’re looking to purchase a polyethylene gas tank, you’ve come to the right place. The Raybuck staff can go over the pros and cons of each option, and help you determine the best solution.

With over 30 years of experience in the aftermarket automotive parts business, we know the industry inside and out. We know all of the options that are available to you, so you’ll get the best products at the best prices for your exact situation.

Contact us today. We can get you started with a polyethylene gas tank for your truck, or any other automotive part you’re looking for.