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Preparing for cold-weather fuel issues

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Preparing for cold-weather fuel issues

Schaeffer's Winter Fuel Additives

By Phil Hamilton, Fuel Additives Manager, and Dawn Cross, Marketing Director

Keep your truck running this winter by taking control of your diesel fuel quality. With loads to deliver and hours of service to adhere to, you don’t want waxing and fuel failures to stop you in your tracks.

Maintaining consistent fuel quality is difficult because so many variables can affect the fuel. Unfortunately, it may not be as simple as always refueling at the same stations. Changes in source, manufacturing and blending may mean the fuel you bought today is chemically different than what you purchased two weeks ago.

Some of this happens during the refining process; variations can occur in the water and paraffin concentrations found in refined diesel fuels. In other instances, the tanker delivering the fuel can cause contamination to occur in the fuel. This happens when the tanker is used to haul all types of fuel, known as switch loading. Inevitability, any remaining fuel from the previous load will mix with the new load.

Cross-contamination can happen onsite at the fueling station. Unless fuel storage tanks are properly maintained, water can make its way into the tanks. This is a double whammy because ultra-low sulfur diesel fuel is prone to moisture. Any water or moisture present can cause rust and corrosion, as well as issues with bacteria in the tanks, all of which can taint the fuel. Throw in some cold temperatures to these scenarios, and it can seem like the odds are stacked against you.

Winterized diesel fuel

Regulatory standards define the minimum performance requirements for diesel fuels. Phrases such as ‘at least,’ ‘no greater than’ and ‘ranges between’ are used to describe acceptable fuel quality. When temperatures plunge, acceptable fuel quality may not be enough to get you through the winter.

Diesel fuel can start to gel and clog filters at 10 ºF – 15 ºF. When the fuel temperature drops below the cloud point, the fuel loses its ability to hold the paraffin (wax) and moisture in suspension. Wax particles will then begin to bond together and become visible—the fuel looks cloudy or hazy. Once the ‘wax cloud’ is present in untreated fuel, the formation of larger wax structures occurs rapidly.

As the wax particles become heavier, they’ll sink to the bottom of the fuel tank. If the wax reaches the tank draw point, it can plug dispenser filters, which eventually prevents the fuel from flowing.

Understanding #1 diesel and #2 diesel

Diesel fuel is available in two main grades, #1 diesel and #2 diesel. #1 diesel is thinner than #2 diesel because of its refining process. Paraffin is removed from the chemical mix, allowing #1 diesel to remain in liquid form. This gives #1 the advantage for cold temperature performance, but fuel economy can suffer if you’re hauling heavy loads over long distances.

On the other hand, #2 diesel contains more energy components and lubricant properties, which allows for better fuel economy. The downside to #2 diesel is its tendency to gel when temperatures drop. Gelling can lead to hard starts and a compromised fuel system.

Even though #2 diesel contains more lubricity than #1 diesel, it still may not be enough to protect fuel systems from wear. Since 2007, the EPA has placed more emphasis on fuel emission performance rather than its lubricity.

During winter months, fuel stations will offer a winter blend of #1 and #2 diesel. However, it’s up to the service stations to decide on the winter blending percentages. The market doesn’t have a standard stations must meet for winter blends. Not only does this create differences in fuel quality, but it can also mean the fuel may not be able to withstand lower temperatures.

Presence of biodiesel

What the EPA mandates and what states require make it hard to keep driving without any fuel problems. On top of that, you may not realize that biofuel is present in every gallon of diesel fuel purchased. Biofuel is great for the environment, but it hinders cold-weather performance. It’s especially hygroscopic, which causes problems in fuel because water freezes faster than wax. Diesel fuel may contain up to five percent biofuel without it being labeled as biodiesel.

Many states require a set percentage of biofuel mixed into every gallon. For example, Minnesota requires #2 diesel to contain at least 20 percent biodiesel (B20) from April 1 to September. From October 1 to March 31, #2 diesel must contain at least five percent biodiesel.

Surviving the winter

Weather is unpredictable, and fuel quality can be unreliable. Don’t take a chance this winter with your fuel quality. Using fuel treated with a multi-functional additive package can mean the difference between driving and gelled fuel.

Some fuel stations will include a premium diesel package already blended into their fuel. Others might offer you the option to blend it yourself. Look for fuel or a fuel additive that includes these performance additives:

  • Anti-gel (cold-flow) coats the wax particles to keep the size from becoming larger than the fuel filter openings. Because wax particles stay smaller and suspendable, it takes less energy or heat to dissolve the wax. Fuel additives with anti-gel packages that provide an improvement of 15 ºF to 20 ºF below cloud point help maintain filterability.
  • Wax anti-settling agent (WASA): WASA offers fuel another layer of protection against extremities as it restricts the wax molecule’s size and density. Settled concentrated wax moves directly to the filter, causing rapid plugging issues. A good WASA will suspend any wax that may have precipitated out of the fuel.
  • Combing cold-flow with a WASA packs a powerful one-two punch against filter clogging. The cold-flow allows the fuel to suspend wax particles longer, giving it more time to be filtered instead of settling at the bottom of tanks. Suspended wax dissolves more rapidly than settled wax concentrations. Using fuel additives with WASA is also recommended if you have above-ground storage tanks or equipment shutdowns for extended periods of the fuel being below cloud point.
  • Moisture control: Water causes a number of fuel headaches, and unfortunately, all fuel contains some water. It’s a good idea to use a fuel additive year-round with moisture control. Most fuels freeze when temperatures reach lower than -20 ºF degrees. However, at 32 ºF, any water present in fuel lines, injectors and filters can start to freeze. Fuel treated with moisture control is crucial during winter months.
  • De-icers: Fuel additives with de-icers can act as a dispersant or an emulsifier that dissolves the water into the fuel to lower the freezing point preventing ice. Watch out for de-icing additives made of alcohols or glycols as those additives can combine to raise the cloud point of fuels.

Helpful tips

When preparing for the winter, make sure you follow these tips to keep your fuel flowing:

  • Partner with a fuel additive company that can provide a quality winter performance package.
  • Learn and adhere to proper tank maintenance procedures.
  • Participate in a fuel testing program to determine proper additive treat ratios and performance recommendations.
  • Storage and shelf life can affect fuel additive performance. Only store products in above freezing temperatures, and only order what you’ll need for the season.
  • The additive should be added at least 15 °F above the cloud point of the fuel to allow for proper mixing.
  • Additives should be splash blended and/or mixed when fuel is being added to the tank so that the additive mixes properly.
  • Pay attention to treat ratios on product labels and datasheets. Some fuel additives may list treat rates that seem reasonably priced until you check the fine print for colder weather treatment.
  • Avoid overtreating your fuel as too much of the performance additives in fuel treatment can hurt fuel economy.
  • Avoid mixing different fuel additive brands in your fuel unless you know they’re compatible. (Also, don’t mix a diesel fuel additive with a gasoline fuel additive. Each product meets a specific need.)
  • Stay ahead of the weather by using multi-functional fuel additives year-round to ensure winter reliability. Some water is inherent in fuel, which can cause rust and corrosion, or cause warm weather issues with bugs or algae.

Performance you can trust

When choosing a fuel additive, look for one that offers you a complete solution for year-round consistent fuel quality like Schaeffer’s Fuel Additives.

Our fuel additives will improve system performance by increasing lubricity lost with sulfur reduction, combat the effects of water, corrosion, long-term storage, the formation of coke in injectors, premature oxidation of fuel and clean deposits from an engine.

Schaeffer uses a jet fuel de-icer and water dispersant that contains no alcohol. Our high-quality additive has a proven record of high performance and reliability to handle any environment. Additionally, our proprietary WASA allows wax to quickly diffuse, so more fuel is able to pass through the filter. This provides more time for the engine to warm up, and once the engine is warmed up, the chances of waxing issues are diminished.

On top of that, we’ve doubled the amount of moisture control in our fuel additives, thus exceeding industry standards for subfreezing performance. With this much moisture control, our fuel additives provide superior moisture removal performance from untreated diesel fuels and eliminate potential icing and waxing issues.

Our fuel additives are built to perform in different weather conditions across the country. Each year, from October to March, we test our fuel additives to document cold-weather performance. The data consistently shows proven cold filter plugging point results. We offer different treatment ratios so you’re only using what you need for your region or driving route.

Let us show you how we can keep your diesels running year-round. Visit or call 800-325-9962