Fleet managers must stay abreast of the latest engine developments and be ready, open, and prepared to adapt and adjust fleet management strategies accordingly. - Photo: Government Fleet

Fleet managers must stay abreast of the latest engine developments and be ready, open, and prepared to adapt and adjust fleet management strategies accordingly.

Photo: Government Fleet

You may not have been around in 2010 when the last major U.S. Environmental Protection Agency regulations and subsequent diesel engine emission technologies were introduced and implemented in all diesel trucks.

If that is you, you are lucky because you missed the transition period when operating diesel trucks, beginning in 2010 and the succeeding months and years, due to the new emissions hardware, became an interesting learning experience and representing a somewhat difficult adjustment period in the lives of fleet managers, technicians, and even service departments.

In that early period, every truck operator, service outlet, fleet maintenance operation and truck dealer was feverishly breaking the code (pardon the pun) on Selective Catalytic Reduction (SCR) aftertreatment systems, learning new terms such as Regen, DEF and DPF, and becoming familiar with a host of new trouble codes, their meanings and the actions required to clear them.

A Transition Period for Diesel Truck Operators

Further and as the years have progressed since 2010, it is safe to presume that no one had any clue as to the extraordinarily high costs this new technology would heap onto our collective fleet ownership costs and downtime calculations.

And while SCR performed best in high-mileage sustained high temperature environments such as in over-the-road trucks, few of us in the public sector, also transitioning to the mandated SCR equipped trucks and unfortunately for us, operated in consistently low-mileage and low temperature and underperforming SCR profiles.

Consequently our fleets, our technicians, our management, our customers and our budgets settled for high cost and significant underperformance of these systems as a result. The SCR aftertreatment system did not and still does not perform well in our public sector applications, to our collective detriment.

That is all about to change! Announced this month and beginning in 2027, the latest EPA GHG3 emissions regulations specifically target public sector diesel powered trucks.

EPA's Phase 3 Standards for Public Sector Diesel Trucks

This quote is taken directly from the EPA’s announcement dated March 20, 2024. It says:

“The final Phase 3 standards apply to heavy-duty vocational vehicles (such as delivery trucks,refuse haulers, public utility trucks, transit, shuttle and school buses and tractors (such as day cabs and sleeper cabs)…”

Public sector fleets are left out no longer! Lucky us…

Implications for Public Sector Fleets: Understanding the Changes

What does this mean for public sector fleets? Hopefully, the following paragraphs will offer both clarity and headwind considerations of which every public fleet should be aware and consider as they formulate their capital acquisition strategy for diesel truck procurement in the coming few years.

Among the major goals of these new regulations is to provide truck OEMs greater incentives to develop alternatives to diesel power and truck buyers greater incentives to acquire EV’s, ZEV’s, and even hydrogen powered units…someday, if and when they become viable.

Most fleet managers agree that regardless of what I called the rush to electrify in a previous article as “electroeuphoria”, diesel power in truck applications will continue to dominate public sectorchassis specifications for many years. If true, it is suggested that public sector entities pay very close attention to how engine makers respond to these new rules.

The “why” is detailed below. Without going down the emissions “rabbit hole” too far, the new standard specifically targets NOx emissions for diesels particularly when operating at low-load and/or at idle when engines are cooler; two characteristics common to public sector truck operation.

Strategies for Adapting to New Regulations: Considerations for Fleet Managers

An additional emissions target for normal operation is included but the major effort is to increase engine temperatures much sooner in an engine’s operating cycle. This EPA rule is the first increase in NOx emission standards since 2010, when aftertreatment systems (e.g. SCR) became ubiquitous. 

Furthermore and assuredly impacting new vehicle costs, this new EPA rule requires a significant extension of emissions control system warranties from the current 100,000 mile limit to 450,000 miles. This extension is designed to assure that the new emission systems will remain effective and functioning within Federal standards for a longer period of time.

Evaluating Diesel Engine Choices for 2027 and Beyond

To comply with the 2010 standards, all engine manufacturers (ex. Navistar) in the U.S. adopted SCR technology as their preferred aftertreatment control mechanism. This universal adoption of one hardware choice made the 2010 transition easier for fleets and service outlets alike all experienced many of the same challenges. Is it likely then that for 2027 and beyond, engine manufacturers will again adopt similar hardware and technology? Not likely, as you will see below. 

Below is a summary of the technologies being considered currently as reported by the engine manufacturers themselves:

  • Cummins:
    • Cummins has received considerable press about their new, fuel agnostic, X15 engine. Also in the wings and likely using similar fuel agnostic technology, is their X10 engine scheduled to be released in 2026.
    • It will feature a 48 volt, belt-driven alternator system to power an aggressive emissions heater to elevate engine exhaust temperatures early in the duty cycle to satisfy the lowload and idle emission standards.
    • Cummins has said the X10 will feature two separate electrical systems, 48v and 12v. On the technology front, Cummins has said their X15 will feature algorithmic on-board oil and filter monitoring to improve engine service timing.
  • Detroit Diesel:
    • Updates to both the DD13 and DD15 engines are expected with higher compression ratios and the introduction of thermocoasting featuring both three cylinder fueling and three cylinder engine braking resulting in retaining high aftertreatment temperature.
  • Navistar:
    • Updates to Navistar's S13 Integrated Powertrain system featuring SCR but without an EGR cooler. The exhaust will flow through the turbocharger and then through a dual stage aftertreatment system to maintain high aftertreatment temperature. Without the EGR cooler, exhaust will contain less soot and particulate matter hopefully resulting in extending DPF life.
  • Volvo/Mack:
    • Both are using a holistic approach combining engine technology innovations with integrated powertrain solutions (I-Torque or mDrive respectively) to modify/exploit engine torque curvesand axle ratios more efficiently. Volvo is adding a new linear exhaust system to its D13 engine offering more ease of service and more efficient DEF delivery.

Early Pre-buying and Delayed Acquisitions

In all cases, engine manufacturers anticipate greater fuel efficiency along with full emissionscompliance. In 2010, actual customer operating experience became the test bed for SCR technology. I can remember dealership techs rushing to our shops when we reported early issues with our 2010 diesels; dealership techs were learning too.

It is hoped that with more time to test these new engines with their customers in advance as is planned, the new technologies will come to market in 2027 with more confidence and reliability. We can only hope…

Clearly from the detail noted above, it is unlikely that the engine manufacturers will be sharing or adopting similar technologies as they did in 2010. For public fleets then, or any fleet considering their vehicle acquisition strategy, it is recommended that careful consideration and understanding be given to selecting engine and/or powertrain combinations for 2027.

Should you consider the alternate procurement strategy of pre-buying chassis in 2025 or 2026, in lieu of 2027 procurements, if your capital budgets will allow?

Given the broad technology variations among engine OEMs expected and as are detailed above, changing engine suppliers from year to year as can happen in the public sector procurement processes, will likely yield significant and costly technical training, maintenance and parts inventory challenges that should be avoided.

Challenges and Opportunities for Public Fleets 

Fleets should be confident enough in their 2027 diesel engine and powertrain choices to consider standardizing on those choices for that model year and for succeeding model years as well. Having a close partnership with your engine and/or chassis provider will likely be more important than ever as you rely on their education and information to help inform your decisions.

A public fleet conversation about engine choices would not be complete if some discussion about capital cost and budgetary expectations were not included. According to a study published by the American Truck Dealers in 2012, the addition of SCR systems alone added $9200, to the price of a new 2010 truck chassis; that represents roughly $13,000, in today’s dollars. 

In the conclusion of that same study, they stated “…the EPA also failed to accurately analyze and project higher truck operating costs, reduced truck reliability, and lower truck fuel economy performance. Consequently, EPA’s mandates resulted in significant and costly marketplace disruptions and reduced regulatory benefits.”

That statement is a cogent summary of the public sector’s collective 2010 emissions transition experience. Have we the luxury of being guardedly hopeful the EPA has learned valuable lessons from that experience? Or is it more likely the EPA will simply depend on the fleet market to adjust accordingly?

Partnering with Procurement and Staying Informed

It is a given that in 2027 and after, diesel chassis will be more expensive, more technologically complicated, perhaps less reliable, require a new motor oil formula (see my previous article on that topic) and may even require a different formulation of DEF than is in use today. Clearly the transition, whenever it occurs in your operation, will impact much more than your entity’s capex.

Should you consider the alternate procurement strategy of pre-buying chassis in 2025 or 2026, in lieu of 2027 procurements, if your capital budgets will allow?

Hadley Benton of Fleet Advantage told Equipment Finance News recently, “In 2027, there will be new regulations that will increase the cost of a truck $25,000 to $30,000. What we’re expecting is a larger “pre-buy” to prepare for that year.”

W.M. “Rusty” Rush of Rush Enterprises, a commercial truck dealer network for both Peterbilt and Navistar trucks, said essentially the same thing on a February 14, 2024 earnings call predicting pre-buys occurring in both 2025 and 2026.

At a recent Volvo media event, Magnus Koeck, Volvo’s Vice President of Brand Management and Marketing was quoted saying, “The pre-buy will start earlier. We’ll see that later this year and in to 2025 and 2026.”

🎯 ACT Research, a leading industry research firm, released a study in 2022 predicting the largest pre-buy ever, beginning in 2025.

Some truck industry professionals are predicting that manufacturing capacity may not meet 2026 routine and pre-buy demands causing an early pre-buying shift to 2025. Although no one yet knows the cost of a 2027 truck chassis from any OEM at this early stage, the aforementioned ACT study predicts price increases of up to $25,000/truck.

The combined impact of the elevated chassis price, the operational impact to fleet operators of adjusting their operations to the new technology, the potential production or parts delays due to supply chain or other causes are all factors that could influence your buying decisions, and that of everyone else in the same marketplace.

Another alternative or companion strategy, that of delaying your 2027 acquisitions, would allow other fleets to experience and break the codes on the new technology and provide engine OEMs the opportunity to experience and correct for real world scenarios all while preventing your fleet from becoming a “test bed” for diesel emissions “Round Two.”

Your truck dealership resources will be learning this new technology just as your technicians will be. Dealership repair outlets may be less responsive than you prefer. Hopefully the EPA is correct that trucks equipped with this new technology will be more reliable, last longer, more fuel efficient, and under more robust warranty coverage, all of which would be beneficial for public fleets.

Your due diligence by staying abreast of the latest engine developments and being ready, open, and prepared to adapt and adjust your fleet management strategies accordingly, will serve your entity well.

Be proactive by advising your procurement team of these changes and partner with them to formulate a procurement strategy that will work for your entity’s benefit. You might consider forwarding a copy of this article to them.

The sooner the better…

About the author
Bob Stanton

Bob Stanton

Fleet Consultant

A charter member of the Government Fleet Hall of Fame, Bob Stanton spent 25 years in government fleet management. He is currently an independent fleet consultant based in Cumming, Ga.

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