Just as the oil in an engine can never rest, lubricant suppliers can never slack off from improving the performance of their products. That is especially the case when it comes to trucking, where demands on engines to run as smoothly and efficiently as possible day after day, year after year, is a de rigueur expectation of fleet owners as well as of engine makers and truck OEMs.
Fleets, of course, never want anything but the best protection and fuel efficiency for their expensive engine investments. And engine makers and truck OEMs will, within a few short years, expect motor oil to contribute to the mandated greenhouse-gas emissions (GHG) reduction and corresponding increase in miles per gallon performance for commercial vehicles.
That's why engine makers have already petitioned for a new American Petroleum Institute (API) oil-service category to be in place by the time the new federal rules go fully into effect. Those rules will start to kick in just three years from now. Under the rules, buses and medium- and heavy-duty trucks as well as pickups and vans will be required to meet federally mandated fuel efficiency levels designed to reduce the amount of GHG emissions they produce.
Developed jointly by the Dept. of Transportation (DOT) and Environmental Protection Agency (EPA) along with input from the trucking industry, environmental groups, and state governments — especially California — the standards will go into effect in stages from 2014 to 2018 and impose different fuel-efficiency targets based on the size and weight of given vehicle types. For example, most tractor-trailers will be required to achieve up to about a 20% reduction in fuel consumption and GHG emissions by model-year 2018, which the government estimates will save up to 4 gals. of fuel for every 100 mi. traveled. Vocational vehicles, including delivery trucks, buses, and refuse trucks, will be required to reduce fuel consumption and greenhouse gas emissions by about 10% by model-year 2018, which should save an average of 1 gal. of fuel for every 100 mi. traveled.
For heavy-duty pickup trucks and vans, separate standards are required for gasoline- and diesel-powered trucks. These vehicles will be required to achieve up to about a 15% reduction in fuel consumption and greenhouse gas emissions by model-year 2018.
Within each truck category, more specific targets are laid out based on the design and purpose of the vehicle; for example, a semi-truck with a low roof vs. one with a high roof. Fuel-efficiency gains will be charted for each year and for each vehicle category and type.
Although it is yet far from certain, it appears very possible a new API oil-service category — one that would supplant the current CJ-4 category — will be developed and put in place to address changes that likely will be made to medium- and heavy-duty diesel engines by the time the rules kick in.
“The industry is currently working its way through the API [oil-classification] process outlined in API 1509 with regards to evaluating the need to develop a new API service category to address the greenhouse gas/mpg regulations that have recently been put in place,” advises Jeff Torkelson, Ph.D., technical manager-commercial & industrial lubricants, Valvoline New Product Development Labs.
“The group working on this is called the New Category Evaluation Team, or NCET, and is made up of representatives from the Engine Manufacturers Assn. (EMA), API and the American Chemistry Council (ACC),” he continues. “Their recommendation will be taken forward to the Diesel Engine Oil Advisory Panel [of the American Society of Testing & Materials (ASTM)] and ultimately API. The formation of NCET is the first step in the process of developing a new category. EMA has asked for a new category of engine oil — now known as PC-11 (for Proposed Category 11) — to be available for first license on Jan. 1, 2016.”
Heading up API's PC-11 NCET is Dan Arcy, OEM technical manager for Shell Lubricants. He explains that the team consists of three member representatives each from API, EMA and oil additive suppliers as well as representatives from industry testing labs.
Each time an NCET is formed, its charter is “to look at all information being presented by engine makers to see how developing and releasing a new API category would affect the marketplace, other existing API categories, and the environment.
“The team must also consider the timing of the request, whether or not there are tests available [to prove it out], and is there sufficient data to support changes in engine design,” Arcy continues. When its work is done, the team makes a recommendation to the ASTM oil panel on whether to proceed with a new category or not.
He adds that the team's recommendation can be a definite “Yes” by consensus or it could be a “No,” but with reasons cited for the denial. At this point in time, Arcy notes, it is too soon to know when a decision will be reached, but “hopefully as soon as possible. There are many stakeholders who have commented on this and the team must take it all into account.”
Valvoline's Torkelson says that along with the impact of the news rules on motor oil, “PC-11 oil will also address concerns that have been raised by EMA. These mainly have to do with newer engine designs already introduced or expected to be introduced into the market in the near future.
“The main parameters that EMA is concerned with … are a more robust oxidation test, a more representative shear stability test, a better aeration test, and a test that incorporates a biodiesel compatibility aspect,” Torkelson adds.
Not every major oil supplier agrees to the blanket assessment held by several formulators that future diesel motor oils will have to be of low-viscosity formulation to ensure the highest mpg performance possible. However, lower-viscosity oil appears to be on the table as the possibility of launching PC-11 is investigated.
“We feel that an extensive industry-wide education program with active participation from members of EMA, API and ACC will be necessary to overcome likely misgivings from fleets and operators that will have a hard time accepting non-traditional heavy-duty viscosity grades such as 5W-30,” points out Torkelson. “The team set up to develop the new API category of oil will ensure that the testing necessary for PC-11 oils is robust — and the group will focus heavily on durability for any lower-viscosity grade oils.”
He notes that Valvoline is “actively field-testing lower-viscosity grade oils to understand durability concerns.” Torkelson adds that Valvoline is already “starting to hear a bit of communication from OEMs actively looking for higher mpg performance from current API CJ-4 oils.”
With that development and with PC-11 in mind, he advises that “lower viscosity is the most significant property that will impact engine oil's contribution to fuel efficiency. Valvoline has been conducting extensive studies … including numerous SAE J1321 fuel-efficiency tests, fleet testing and engine stand testing, and is at the forefront of understanding how formulation parameters can influence fuel efficiency. Other formulation options other than just lower viscosity can be used to influence fuel efficiency, but low viscosity is the major factor.”
“Between 2014 and 2018, we know the rules will get stricter,” says Mark Betner, product manager-heavy-duty lubricants for Citgo. “We're talking 20% more fuel efficient on a carbon dioxide per ton mile basis [of measurement]. That bogie has brought engine makers back into the discussion about motor oil.
“As truck OEMs look at everything ahead of the new GHG and mpg rules taking effect, why wouldn't energy-efficient lubricant formulations be considered?” He says the only caveat that will matter is that the contribution of the oil to improving truck miles per gallon will have to be cost-effective overall.
According to Betner, it pretty much goes without saying that the industry will have to look at lower-viscosity oils, but it will have to do so “holistically” by factoring in all aspects of their performance, including drain intervals.
“If all these factors come together,” he advises, “it's realistically possible a new oil-service category could be introduced by 2016 that could include fuel-efficiency benefits.”
Betner cautions, however, that API categories aside, before there will be widespread acceptance of low-viscosity oils by fleet owners, the supplier community will have to work to overcome what he calls the ‘viscosity-fear syndrome’ held by many truck operators: the unfounded concern that viscosity grades lower than 15W-40 will not provide the same degree of engine protection.
Jim Gambill, manager of direct marketing for Chevron Lubricants, says it's a “known fact” that lowering viscosity will increase fuel efficiency, noting that some suppliers claim as much as a 2% increase for a Class 8 rig. Chevron, though, is more conservative. “We put the fuel-efficiency improvement with a 10W-30 oil vs. a 15W-40 at 1% for a Class 8. That's with durability maintained and allowing for OEM-approved oil-drain intervals.”
He says that “with midsize trucks and their 6L to 8L engines, the proof is deeper as their rpms are higher and they typically idle more. For these trucks, there are claims of a 4 to 5% improvement in mpg that we agree with as well.”
LONG ROAD AHEAD
Gambill points out that lower-viscosity oil still has a ways to go to gain wide acceptance from fleets as 15W-40 oil accounts for 93% of the oil sold in the trucking market.
“There is some speculation on our part that whether or not the next oil category will be driven by fuel efficiency or durability or both, our customers have said they clearly want both,” he continues. “To achieve this, we may have to look at all the lubricant and fluid links in the chain — go bumper-to bumper — to attain the sort of mpg improvement that may be sought to meet the potential new rules.”
Indeed, according to Gambill, when Chevron looked at what could be done to boost fuel efficiency on off-road equipment, it found that making changes in hydraulic oil alone could boost mpg by 8%. “We'll continue to look at places [to make improvements] where we had not before, but we also must always balance the risks to operators against the rewards they may attain.”
When it comes to customers, he adds, “we have noted that the average age of trucks has climbed with many now 10 to 15 years old. We have to think about these operators as well. They may be doing fine with fuel efficiency, but engine durability is their big issue.”
Shell's Arcy says fleets can switch from a 15W-40 to a lower-viscosity oil anywhere in North America “with no problems at all” — but they should check first with their engine maker on their specific guidelines.
“There can be a 1 to 2% mpg gain from moving from a 15W-40 to a lower-viscosity oil,” he states. “There's a definite fuel savings when comparing apples to apples without compromising oil performance, including engine durability and drain capability. But actual savings will vary by application, by truck and by engine, and by the model year of the engine as well.”
Chevron's Gambill advises that the key thing to keep in mind in all these discussions is that “oil must be formulated properly for the given situation — the truck and its application. Fuel economy is important to everybody, but oil's main role remains ensuring engine durability.
“When you think about it,” he adds, “the number-one way to be green is to make things last as long as you can.”