Work Truck Logo
MenuMENU
SearchSEARCH

How Changing Emissions Standards Affect Work Truck Fleets

Many industries are making it a priority to reduce greenhouse gas emissions, as national standards and public expectations continue to change. The work truck industry is among those most affected by this push.

by Cari Groppel
May 9, 2019
How Changing Emissions Standards Affect Work Truck Fleets

Since the implementation of Tier 4 regulations, many work truck fleets are seeing increased downtime for engine regeneration and more time and money spent on maintenance.

Photo courtesy of Miller

4 min to read


Many industries are making it a priority to reduce greenhouse gas emissions, as national standards and public expectations continue to change. The work truck industry is among those most affected by this push.

According to 2016 data from the Environmental Protection Agency (EPA), the transportation sector accounted for the largest portion (28%) of total greenhouse gas emissions in the United States, followed by electricity and industry.

Ad Loading...

Among the transportation sector, light-duty vehicles were the largest source of emissions at 60%. Medium- and heavy-duty trucks were the second-largest source of emissions in transportation at 23%. Most work trucks and service fleet vehicles fall into the light- and medium-duty categories.

As the work truck industry works to reduce emissions and meet changing regulations, new technologies and equipment can help save fuel and decrease emissions — resulting in a greener, more efficient fleet.

Changing Emissions Regulations 

Vehicles that are more efficient and use less fuel produce fewer emissions and help contribute to cleaner air. As part of this movement, the EPA’s Tier 4 regulations are a significant reduction in the allowable levels of exhaust emissions from diesel engines. Any new diesel engines produced must meet these reduced emissions requirements. And, Tier 4 is likely not the final chapter in emissions regulations, as more stringent standards could be on the horizon.

While the EPA regulations address emissions at a national level, laws governing vehicle smog checks are handled at the state and local levels. Some states have no requirements for smog testing; other states require emissions testing at varying intervals (often every two years) depending on vehicle type.

Among the transportation sector, light-duty vehicles were the largest source of emissions at 60%. Medium- and heavy-duty trucks were the second-largest source of emissions in transportation at 23%.

Photo courtesy of Miller

Tier 4 Impact on Work Trucks

Since the implementation of Tier 4 regulations, many work truck fleets are seeing increased downtime for engine regeneration and more time and money spent on maintenance.

Ad Loading...

Some fleets aren’t running Tier 4-compliant trucks yet and are still using model-year trucks made before the regulations were put in place. As older diesel trucks reach the end of their useful life, fleets will have to replace them with Tier 4-compliant vehicles.

So, what is driving the increased downtime and maintenance for Tier 4 trucks? These engines use a diesel particulate filter (DPF) to trap soot from engine exhaust gases. The DPF requires periodic cleaning through regeneration to maintain emissions reduction performance and fuel efficiency.

How frequently DPF regeneration must happen depends on several factors, including how much time a work truck spends idling. The more time a truck engine idles — such as to power air compressors, pumps, hydraulic cranes and other jobsite tools with a PTO-driven system — the more clogged the filter becomes and the more frequently it requires regeneration.

Driving at uninterrupted highway speed is one way to automatically regenerate the engine. Another option is to perform a parked regeneration with the engine running. This cleaning cycle can result in up to an hour of downtime for the truck.

The regeneration cycle heats and burns off much of the material blocking the filter. The remaining particulate matter not burned off through regeneration can lead to increased regen time, poor fuel economy, reduced power output and costly engine damage. This remaining material can be cleaned through a specialized process that requires removal of the DPF from the exhaust system and shipment to a servicing facility. Some companies will come to you to replace a DPF on-site, though this is a costly option. Each DPF can cost thousands of dollars, so any efforts that prolong filter life can help reduce operating costs and downtime.

Ad Loading...

Finding ways to reduce work truck engine idling can help reduce or eliminate many of these headaches.  

Photo courtesy of Miller

How Idling Increases Truck Downtime

Because Tier 4 engines are not designed to idle constantly, this presents a challenge for work trucks that must idle all day to power air compressors, pumps, hydraulic cranes, and other jobsite tools.

As mentioned, a parked regeneration can result in up to an hour of truck downtime, but not performing regeneration frequently enough can lead to even longer and more costly downtime. Engine performance may be reduced if too much particulate builds up, and the truck may even shut down if the regeneration warning is ignored or missed when the DPF is full. At this point, the operator cannot regenerate the DPF, and the truck must be taken to an authorized dealer to have the DPF removed so it can be cleaned or replaced — a process that can take several days.

Finding ways to reduce work truck engine idling can help reduce or eliminate many of these headaches.  

EnPak A30GBW power systems from Miller Electric Mfg. LLC provide compressed air, electrical power, battery charging, and welding while also delivering power to support 12-volt DC needs — all while the truck’s engine is turned off.

Additional technologies ensure the unit’s engine runs at the appropriate speed when needed to meet demands, which results in fuel savings, lower emissions and decreased maintenance.

Decrease Engine Idle Time & Emissions 

Reducing truck engine idling also helps lower vehicle emissions and fuel use. All-in-one work truck power systems allow service technicians to turn off their work trucks and still run the tools needed to get the job done efficiently.

With an all-in-one, truck engine idle time can be reduced by 75% — significantly reducing engine emissions, fuel costs, and maintenance needs.

Ad Loading...

Technology to Meet Changing Standards

Changing emissions standards and the EPA’s Tier 4 regulations for diesel engines have changed the game for work truck fleets. But there are technologies and equipment available that help operations reduce emissions and save fuel, while improving productivity and efficiency.

As emissions regulations continue to evolve, all-in-one power systems can help fleets stay ahead of the curve — substantially decreasing truck engine idle time, reducing maintenance needs, extending chassis life, and saving money.

About the Author:  Cari Groppel is the market development manager for Miller Electric Mfg. LLC.

Subscribe to Our Newsletter

More Green Fleet

Artist rendering of an ev charging facility from an overhead view.
Green Fleetby News/Media ReleaseApril 16, 2026

EV Realty Opens Major Truck Charging Hub in California’s Inland Empire

EV Realty’s San Bernardino Powered Properties’ truck charging hub, which has now opened, can serve over 200 medium- and heavy-duty trucks per day.

Read More →
Closeup photo of an EV charger plugged into an EV, with white logo for WEX.
Green Fleetby News/Media ReleaseApril 13, 2026

WEX Launches Solution to Close the EV At-Home Charging Visibility Gap for Fleets

WEX unveiled its EV At-Home with Vehicle Fraud Protection, which ensures accurate and secure reimbursement for at-home charging.

Read More →
Woman and two men standing holding paperwork agreements they have signed with logos for Daimler Truck, Toyota, and Volvo over their heads.
Green Fleetby News/Media ReleaseApril 6, 2026

Toyota Motor Corporation to Join Daimler Truck & Volvo Group in Fuel Cell Joint Venture Cellcentric

Toyota intends to join Daimler Truck and Volvo Group as an equal shareholder in Cellcentric. All three shareholders intend to further strengthen Cellcentric as a leading manufacturer of fuel cell systems for heavy-duty commercial applications.

Read More →
Ad Loading...
Terminal truck hauling a container trailer with a cargo ship and windmill in the background.
Green Fleetby News/Media ReleaseApril 3, 2026

Volvo Penta Electric Drivetrain Powering Terminal Tractors

Volvo Penta and Volvo Financial Services (VFS) have partnered to support one of Northern Europe's largest shipping and logistics companies in its ambition to transition to electric terminal tractors.

Read More →
Two men stand together holding a certificate award with large commercial trucks in the background.
Green Fleetby News/Media ReleaseApril 1, 2026

PacLease in Dallas Awarded Dallas-Fort Worth Clean Cities Award

PacLease in Dallas, Texas, received a Clean Cities Award from the Dallas-Fort Worth Clean Cities Coalition. PacLease invested in two fast-charging pedestals, one located in Dallas and the other at its sister location in Grand Prairie.

Read More →
Step van driving down road with large orange headline +20,00,000 miles.
Green Fleetby News/Media ReleaseApril 1, 2026

Workhorse Electric Vehicles Surpass 20 Million Miles

More than 1,100 Workhorse trucks, buses, and shuttles have displaced the use of 2.3 million gallons of gas and prevented the emissions of 45 million pounds of CO2. Those vehicles have amassed more than 20 million miles combined.

Read More →
Ad Loading...
Image of a row of EV charging stations and an inset image of a screenshot from a computer and from a smartphone showing charging data.
Green Fleetby News/Media ReleaseMarch 31, 2026

Independent Review Validates Greenlane’s Data Security & Compliance

Greenlane's security controls were independently verified as operating effectively across a nearly year-long audit period. Achieving both SOC 1 and SOC 2 Type 2 compliance demonstrates that Greenlane meets the data security standards enterprise fleet operators require from a charging partner.

Read More →
Man standing in front of an image of a blue-tinted box truck with logos for Work Truck and Truck Chat, and a yellow headline, Meet Harbinger's HC Series Cab.
Green Fleetby Wayne ParhamMarch 30, 2026

Harbinger CEO Explains New Low-Cab-Forward Truck

Join Work Truck as we tour Harbinger Motors’ new HC Series cab, a medium-duty low-cab-forward work truck available in electric and hybrid configurations, with CEO John Harris.

Read More →
Computer screen with software and numbers displayed.
Green Fleetby Wayne ParhamMarch 27, 2026

ChargePoint Launches Tools to Improve EV Charger Management

ChargePoint’s new Premier Care supports large or complex charging networks by providing concierge services to streamline operations, and the new Support Portal transforms the customer support experience into a transparent self-managed hub.

Read More →
Ad Loading...
Work Truck Week 2026 Work Truck from the Show Floor FCCC
Green Fleetby News/Media ReleaseMarch 16, 2026

FCCC Collaborates with Roush On Next-Gen Engine

FCCC will work with Roush Power Systems, a recently formed division of Roush, to integrate the new GM 6.6L gas engine into its chassis products across a range of applications and markets.

Read More →