In 2005, Government Fleet and other trade publications ran articles about the coming mandate for a new diesel fuel, Ultra Low Sulphur, and the coming changes in both 2007 and 2010 diesel engines. Little did we in government fleet, or the industry as a whole, realize then how greatly those changes would impact vehicle costs in both capital and maintenance.
Who could have predicted that exhaust system maintenance, a system that was mostly an afterthought in our overall maintenance strategies prior to 2010, would become among the most troublesome and costly systems to maintain following the implementation of the mandate?
Beginning in 2021, EPA requirements for efficiency and NOx emissions, beyond current federal requirements, will bring yet another round of capital and operational changes to our industry.
Unlike 2007 or 2010, these changes will be with us in three stages – 2021, 2024, and 2027 – as OEM requirements for greenhouse gas (GHG) emissions and fuel efficiency gradually become more stringent.
So, what will these changes mean for government fleets? Because government fleets are so diverse in vehicle populations and mission profiles, some could argue our fleets are more directly impacted than most.
Unlike previous mandates, the regulations for 2021 and beyond separate truck type categories into heavy-duty (Class 8), vocational, or medium-duty and heavy-duty pickups, all of which apply to governments as most operate considerable truck populations in each category.
I can remember when the government fleet I managed in 2010 received our first delivery of 2010 compliant trucks. We never had better service from our truck engine OEM than during those first few months. The truck service outlets were learning just as much as we were about how to diagnose and repair engines with this new technology.
This separation of classifications indicates medium-duty trucks and pickups are receiving the attention that was lacking in the 2010 mandate.
This author’s opinion, then and now, is 2010 engine testing had not been engaged adequately in vocational/government spaces, and government fleets paid a high price not only in both the steep learning curve of maintenance, operation, and repair, but also by becoming the “test bed” for technology heavily tested only in over-the-road applications.
Separating medium-duty trucks and heavy-duty pickups within the new standard acknowledges their lower speed and engine temperature profiles. In these classes, the new requirements place little emphasis on changes in engine technology, and greater emphasis is placed on matching engine and powertrains to maximize fuel efficiency, lightweighting, using low-rolling resistance tires (LRRs), and tire pressure management through the use of tire pressure monitoring devices.
Due to the introduction of large gasoline engines in vehicle Classes 4 through 7, it’s likely gasoline engines will become a more operationally acceptable alternative to government fleets than diesel engines in these smaller classes of trucks. Gasoline power plants are typically easier and less expensive to maintain, and given the tight market for technical expertise in the shop, gasoline engines may become the preferred alternative for reasons of uptime and simplicity.
Further, because many governments were early adopters of electric vehicles, have a more robust charging infrastructure in place than most fleets, and operate trucks within a tight distance radius, governments may be more prone to consider battery electric and/or hybrid trucks as they become more available.
Even if electric truck adoption remains weak, especially in the early years of this transition, much of the common technology featured in electric and hybrid vehicles will likely migrate to medium-duty classifications in both diesel and gasoline chassis. In order to meet new fuel efficiency standards, mild hybridization, cylinder deactivation, engine start/stop technology (possibly including energy recovery such as regenerative braking), and steering and/or brake by wire can be expected in Class 4 through 7 trucks.
Because OEMs are ultimately responsible for offering engine and powertrain combinations that fully meet the newest standards, it will be interesting to learn how each solves the efficiency and CO2 mandates in the medium-duty classifications as the standards become increasingly more restrictive in the three upcoming stages this decade.
The new standard in the heavy-duty arena favors greater migration from manual to automated transmissions. In the smaller classifications, especially for governments, the favored transmission will continue to be fully automatic. Government truck buyers should be particularly sensitive, especially in the 2021 and 2022 model years, to ascertain how fully their new truck of choice equipped with an automatic transmission meets the new standards. Transmission OEMs are currently developing eight- and nine- speed automatic transmissions that may meet the standards more easily. They likely will not be on the market within the next couple of government procurement cycles.
In addition to changing transmission technology, government buyers will also see changes soon in axle technology designed to improve fuel efficiency and motive power disbursement.
Given the emphasis on fuel efficiency in the new standards, engine sizes in this sector will likely shrink slightly. This is unlikely to greatly impact government fleets, as governments are less likely to favor a 14L diesel engine but instead opt for 10L engines or slightly larger.
The recent buyer’s trend toward downsped engine packages to lower revolutions per minute (RPMs) will continue and likely increase intake rate for trucks sold this year and in 2021.
Heavy-duty trucks will feature a greater emphasis on aerodynamic designs to lessen wind resistance as a fuel-efficiency measure. Government fleets care little about this aspect, meaning this will likely not be a procurement factor.
If Class 8 trucks feature LRRs as yet another strategy to meet the new standards, this shift will impact all buyers of new trucks including governments. The benefits seen from the use of LRRs for governments is unlikely to be realized, and the cost of their implementation should be closely monitored by governments to determine their efficacy in a government application of low miles and speed.
New Technology on the Horizon
Given the standard represents a six-year evolution of increasingly rigid requirements, new, and even some older, technologies being tested on diesel engines today have promise for the near-term future. Fleets should stay abreast of the deployment of these technologies, especially for the 2024 and 2027 engine families.
Thermal management, a missing priority in 2010 technology, is getting a lot of attention and testing within the diesel engine manufacturing community. For vocational units, the lack of thermal management has contributed to the extraordinarily high failure rate of selective catalytic reduction (SCR) systems to date. The technology being considered includes heated aftertreatment systems, engine throttling, and even flow-bypass filtration, all to assist the engine in maximizing the effectiveness of the aftertreatment system by keeping temperatures high.
In addition to these seemingly downstream measures, certain active engine performance and operations technologies are also being tested. For instance, variable valve actuation (VVA), a system that uses oil pressure to control the travel distances and timing of the exhaust and intake valves, is likely to be featured in upcoming diesels. VVA is a thermal management strategy that can modify air flow or completely deactivate cylinder operation to raise the temperature of still operating cylinders.
The biggest danger to an SCR system is lack of heat. Low operating temperatures prevent the SCR system from operating efficiently, and, consequently, limits the system’s ability to burn NOx and other particulates causing premature failures of which government fleet managers are all too familiar.
Yet another strategy being tested is dual SCR passive thermal management. This term may strike fear in the minds of fleet managers given their history with the current SCR technology. Nevertheless, this system uses the same technology, but adds a smaller SCR catalyst to the exhaust side of the turbocharger. Locating it close to the turbo facilitates faster exhaust heating.
Government Fleet Procurement Strategy Considerations
In the old days, especially prior to 2000, the range of options available to the truck buyer was seemingly endless. The “options funnel” has continued to narrow as the value of OEM efficiency and factory inventory management have served to help lower production costs. The option strategy funnel will narrow further as OEMs offer engine, transmission, and rear axle combinations that meet the standards of which customer deviation will not be offered.
Based on these newest standards, offered on page 20 are procurement and equipment evaluation strategies government fleets should consider as they navigate this new normal.
The mating of powertrain components will be a key factor in truck procurement moving into 2021 and beyond. OEMs will offer a more limited range of powertrain options to assure they comply with the new standards to which they will be held accountable. Consequently, fleet buyers and specification writers must be open-minded and willing to compare, contrast, and consider a likely more limited range of powertrain choices.
Consider Including Downsped Engine Packages
While downsped engines are popular in line haul applications, the technology applies to vocational trucks as well. This technology may add a few hundred dollars to the cost of a truck, but the benefits in fuel economy, engine noise, lower speed thresholds, and higher torque will more than offset the capital cost.
Maintenance Processes Will Change…Again
Meticulous attention to oil quality, change intervals, and oil level management will become even more important as engine modifications such as VVA are deployed.
Attention to tire management, low rolling resistance (LRR) tire introduction, and air pressure monitoring will become even more important. Although there is little chatter about retreading LRRs, there is no doubt this product will become an integral part of aggressive tire management programs.
Greater attention will be given to the management and maintenance of SCR systems in new trucks and their ability to operate efficiently at a high enough temperature to be fully effective. As such, more sensors and diagnostic processes will, no doubt, be added.
Consider Gasoline Alternatives
Gasoline engines, especially in Class 6 and 7 trucks, have become a viable and cost-effective alternative to diesel. The attractions of having a no SCR system, better driving performance, and lower capital cost should not be discounted by governments.
For the past several years, governments have been buying Class 4 and 5 trucks, paratransit buses, and emergency vehicles equipped with gasoline in lieu of the former standard diesel engine. Those same benefits are now available in large chassis configurations.
Consider Pre-Buys in 2023 & 2026
New technology typically means new challenges and higher costs both in maintenance and operations. Although the industry is quick to state fuel savings that will accrue from new engine efficiencies will offset the increased capital cost of acquiring new trucks, it’s not possible yet to predict which technologies will be deployed and whether they will feature less intensive maintenance attention.
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