This story appears in the Dec. 12 print edition of Transport Topics.
As the cold temperatures of winter set in, fleets and fuel providers are using a variety of methods to prevent fuel gelling, which can lead to truck breakdowns and maintenance headaches.
Cold weather can cause the paraffin wax in diesel fuel to gel and clog an engine’s fuel filters — a problem that can be quite difficult to solve.
“Once the fuel in a truck gels up enough to clog the fuel filter, it takes a lot of time to fix the issue,” said Jon Andrus, vice president of fleet administration at Doug Andrus Distributing, a truckload carrier based in Idaho Falls, Idaho. “We may have to change the fuel filter several times in the process of getting the gel out of the system. Sometimes we have to tow the truck to our shop and let it thaw out.”
Fortunately, fleets have several options to prevent gelled fuel, including “winterized” diesel, fuel filters with heaters and engines that start automatically as needed.
Winterized diesel can involve blending two types of diesel, using fuel additives, or both. Most diesel fuel in the United States is ultra-low-sulfur diesel, also known as No. 2 diesel, said Bill Dawson, vice president of maintenance operations and engineering at Miami- based Ryder System Inc.
No. 2 diesel starts to gel at about 15 degrees Fahrenheit, which is known as the fuel’s cloud point, Dawson said. No. 1 diesel is “essentially kerosene, which is lighter and has a lower cloud point,” he said. “When No. 1 diesel is added to No. 2 diesel, the blended fuel has a lower cloud point than No. 2 diesel alone, so it’s less susceptible to gelling.”
Companies that rent or lease Ryder trucks can buy fuel from Ryder. In the winter, this is Ryder’s winter blend. In addition to blending the two types of diesel, Ryder uses a fuel additive designed to help prevent gelling.
“The specific recipe that we use depends on the location and the weather,” Dawson said. “The colder it is, the more additive we use.”
However, the use of fuel additives is not embraced across the industry. Some truck manufacturers warn against it, but others see it as an acceptable option.
Jeanelle Morris, a materials engineer at Navistar Inc.’s International Trucks, said additives should be regarded as medicine for the fuel.
“Like medicine, they should be prescribed by an expert who has diagnosed the problem,” she said. “Indiscriminate use of additives can do more harm than good.”
In Warren, Michigan, where James Burg Trucking Co. is based, winters can be severe.
“Around mid-November, we start treating the fuel in the fuel storage tanks at our facility with an anti-gel additive,” said Jim Burg, the company’s president. “Some of our drivers have to fuel on the road, so we supply them with quarts or gallons of the additive so that they can treat their fuel as needed.”
Major truck stop chains use additives to create winterized diesel.
Love’s Travel Stops uses a proprietary additive in its fuel when the season calls for it, said spokeswoman Kealey Dorian. “This additive allows our fuel to continue flowing even during low-temperature and often harsh winter conditions.”
Pilot Flying J adds “cold flow improvers” to its diesel in the winter. The additive keeps the paraffin wax from forming large crystals that can clog fuel filters, a company spokesman said. “By keeping the wax crystals smaller and separated, the diesel fuel is able to pass through a fuel filter.”
The diesel sold by TravelCenters of America is treated all winter in the colder regions of the country and as needed in other areas.
“We splash blend additive to a specification that protects the diesel fuel against severe winter conditions,” said Tom Liutkus, TA Petro’s senior vice president of marketing and public relations.
Sometimes, fleets also take extra precautions.
“We issue an anti-gel additive to our drivers all winter long so that they can add it to their tanks as needed,” Andrus said. “If they’re fueling in the northern states in the winter, the fuel is treated, but we give them the anti-gel additive to be safe. If they’re in really cold weather, such as below zero, we tell them to go ahead and throw the anti-gel additive in, even if they have fuel that’s been treated.”
Kelly Gedert, manager of powertrain and components marketing for Daimler Trucks North America, warned that overtreatment of fuel actually can cause filter plugging due to an excessive amount of anti-gel material.
“We find that additives cause more issues than they solve,” Gedert said. “The most effective means of improving cold weather operability of diesel fuel is a blend between No. 2 and No. 1 fuel.”
Peterbilt Motors Co. does not recommend fuel additives, said Mike Conroy, director of field service for the truck maker. But he acknowledged that it may be necessary as a temporary solution.
In that case, “general industry guidance is use a high-quality and EPA-approved brand, use the additive for the minimum amount of time necessary, follow the additive manufacturer’s instructions and refuel with the appropriate grade fuel as soon as possible.”
Truck makers also offer ways to keep the fuel heated to avoid gelling when an engine isn’t running.
An option on some Kenworth models is an auto start-and-stop feature. In addition to monitoring the batteries when the engine is turned off, the system “also monitors oil temperature, starting the engine when the temperature falls below a predetermined level,” said Kevin Baney, chief engineer at Kenworth Truck Co., noting this helps prevent fuel from gelling.
The engines on Freightliner trucks, DTNA’s Gedert said, are designed to recirculate a large percentage of fuel. “Fuel returned from the hot injectors is circulated right back into the system, and a large amount of the fuel supplied to the filter module is routed back to the tanks to heat all of the fuel up.”
The most important factor in preventing diesel fuel from gelling is the fuel itself, said Conroy of Peterbilt.
Peterbilt encourages customers who regularly operate in cold climates where gelling can occur to spec’ their trucks with fuel filter, line and tank heaters, he said, noting Peterbilt factory installs these options.
Both Volvo Trucks and Mack Trucks offer fuel-heating options.
“In cold climates, our primary fuel filter is available with an electric preheat or electric heat option,” said Jason Spence, product and marketing manager for longhaul at Volvo. The truck maker also offers an optional fuel tank heater.
“For 2017, Volvo models equipped with Volvo and Cummins engines feature a new return fuel recirculation valve, which transfers fuel back to the primary filter instead of sending it to the fuel tanks first, which would allow it to cool off,” he said.
Scott Barraclough, technology product manager at Mack, said the company offers in-tank fuel heaters, as well as heated fuel filters to help address potential issues with diesel fuel in cold weather.
Davco Technology, which makes the fuel filters that are used in many trucks today, offers several heating options: a 12-volt fuel heater, an overnight heater and a coolant heater. Its filters have a transparent dome on the top, which makes it possible to see if the fuel inside the unit has gelled.
“If the operator does a visual inspection of a unit [that has the 12-volt heater option] and sees that paraffin wax is starting to form, you can turn the ignition on, and in 10 or 15 minutes, you will see all of the paraffin wax melt,” said Rich Rhoney, manager of sales and service support at Davco.
The overnight heater keeps the fuel in the unit warm while the truck is parked.
“You can take out the extension cord and plug it into a wall outlet,” Rhoney said. “This will keep the fuel from gelling during overnight parking. There is also a coolant heat option that uses the heat of the running engine to maintain fuel temperatures while driving.”
Ultimately, every fleet needs to prepare for possible fuel problems during winter, Ryder’s Dawson said.
“Whether you are managing your own fuel or you’ve outsourced that fuel, you have to have a plan around acquiring the right blend of fuel or you’re going to be in trouble,” Dawson said. “You have to be sure you have a preventive maintenance plan in place that ensures that the vehicles are ready for use. If you do those things and you practice an ounce of prevention, then you can expect to have a good winter.”
Ryder’s Supply Chain Solutions business unit ranks No. 13 on the Transport Topics Top 100 list of the largest U.S. and Canadian for-hire carriers.