Heavy Duty Trucking Logo
MenuMENU
SearchSEARCH

Analysis: Clean Diesel Truck Adoptions Jumping in Southwest, Northwest

Nearly half the commercial trucks operating in EPA Regions 9 and 10 are now powered by the newest-generation of Near-Zero Emissions diesel engines, according to analysis by the Diesel Technology Forum.

by Heavy Duty Trucking Staff
July 23, 2021
Analysis: Clean Diesel Truck Adoptions Jumping in Southwest, Northwest

Nationwide, the newest near-zero-emissions diesel trucks now make up almost half of the more than 11 million diesel-powered commercial vehicles on U.S. roads

Image: Diesel Technology Forum

2 min to read


Nearly half the commercial trucks operating in EPA Regions 9 and 10 are now powered by the newest-generation of Near-Zero Emissions diesel engines, according to Diesel Technology Forum ‘s analysis of 2020 U.S. vehicles in operation data (Class 3-8) provided by IHS Markit.  

Ad Loading...

Those two EPA regions take in the entire Southwest and Northwest as well as Hawaii and Alaska. Now standing at exactly 43.3%, the share of new technology diesel trucks in the regions expanded by 6.6% between July 2019 and December 2020.

Ad Loading...

Nevada and Washington both saw a 19% increase in the number of new technology diesel trucks in operation in their states.  California saw a 17% increase in the number of new technology diesels in operation compared to 2019.

Diesel Technology Forum pointed out that beginning in 2010, all new heavy-duty trucks have been equipped with selective catalytic reduction (SCR) and particulate control technologies. DTF said these combine to achieve stringent Environmental Protection Agency emissions requirements for nitrogen oxide (NOx) emissions of no more than 0.20 grams per brake horsepower hour (g/BHP-hr).  This is in addition to particulate matter (PM) emissions levels of no more than 0.01 g/BHP-hr.

Almost 50% nationwide

Nationwide, the newest, cleanest, near-zero-emissions diesel truck technologies now make up almost half of the more than 11 million diesel-powered commercial vehicles on U.S. roads, per the DTF analysis.

Since 2007, these newest-generation diesel trucks have eliminated 202 million tons of carbon dioxide (CO2), 27 million tons of NOx, and saved almost 20 billion gallons of diesel and 472 million barrels of crude oil.  “Put into context,” DTF said in a press release, “the emissions and fuel savings attributable to new-generation diesel engines in commercial trucks equates to making 43 million cars all-electric or creating 42,000 wind turbines on land five times the size of Washington, DC.”

DTF also noted that by 2030, thanks to the continued increase of newest-generation diesel-powered vehicles, these savings are projected to grow to 1.3 billion tons of CO2, 47 million tons of NOx, 2.7 million tons of PM, 130 billion gallons of diesel, and 3.1 billion barrels of crude oil.

Ad Loading...

According to Vehicles in Operation Data (2019-2020) from IHS Markit, a total of 15 states are at or above the national average for the percentage of clean diesel Class 3-8 commercial vehicles (all U.S.: 49%) while 23 states are growing their clean diesel fleets faster than the national average (all U.S.: 6.3%) A full state-by-state breakdown is available on the DTF website: https://www.dieselforum.org/in-your-state.

More Fuel Smarts

Solar panels on top of a red Class 8 truck sleeper cab
Equipmentby Deborah LockridgeMarch 15, 2026

Vanair Introduces Solar, Battery Power Ecosystem for Class 8 Trucks

The company’s expanded EPEQ ecosystem includes flexible solar panels, lithium batteries, hydraulic power systems, and a portable fast charger for electric trucks.

Read More →
HDT Talks Trucking thumbnail saying: NACFE's Messy Middle: Which Fuel Wins?
Fuel SmartsMarch 11, 2026

Run on Less “Messy Middle” Data Shows Multiple Paths for Truck Powertrains [Listen]

Listen as Mike Roeth of the North American Council for Freight Efficiency shares insights into battery-electric trucks, natural gas, biofuels, and clean diesel on this episode of HDT Talks Trucking.

Read More →
YouTube thumbnail with Mike Roeth of NACFE saying "NACFE's Messy Middle: Which Fuel Wins?"
Fuel Smartsby Deborah LockridgeMarch 11, 2026

Run on Less “Messy Middle” Data Shows Multiple Paths Forward for Truck Powertrains [Watch]

NACFE's Run on Less - Messy Middle project demonstrates the power of data in helping to guide the future of alternative fuels and powertrains for heavy-duty trucks.

Read More →
Ad Loading...
Mike Kucharski, vice president, JKC Trucking.
Fuel Smartsby Jack RobertsMarch 10, 2026

Trucking Executive Warns Fuel Spike from Middle East Conflict Hitting Fleets Fast

Mike Kucharski, vice president of refrigerated carrier JKC Trucking, says diesel price jumps tied to global instability are squeezing carriers already struggling with weak freight rates.

Read More →
A mechanic in a workshop leans over the open engine compartment of a large yellow vehicle, inspecting components while holding a tablet.
Sponsoredby Kristy CoffmanMarch 9, 2026

Smarter Maintenance Strategies to Keep Trucks Rolling

In today’s cost-conscious market, fleets are finding new ways to get more value from every truck on the road. See how smarter maintenance strategies can boost uptime, control costs and drive stronger long-term returns.

Read More →
Group of researchers and engineers standing next to an electric heavy-duty truck used in Purdue’s wireless charging project.
Fuel Smartsby News/Media ReleaseFebruary 3, 2026

Researchers Demonstrate Wireless Charging of Electric Heavy-Duty Truck at Highway Speeds

Purdue researchers demonstrated a high-power wireless charging system capable of delivering energy to electric heavy-duty trucks at highway speeds, advancing the concept of electrified roadways for freight transportation.

Read More →
Ad Loading...
Illustration showing diesel exhaust fluid pump sign and EPA headquarters
Equipmentby Deborah LockridgeFebruary 3, 2026

EPA Wants to Know: Are DEF De-Rates Really Needed for Diesel Emissions Compliance?

The Environmental Protection Agency is asking diesel engine makers to provide information about diesel exhaust fluid system failures as it considers changes to emissions regulations.

Read More →
SponsoredFebruary 1, 2026

6 Dashcam Tactics to Improve Safety & ROI

6 intelligent dashcam tactics to improve safety and boost ROI

Read More →
Fuel Smartsby Deborah LockridgeJanuary 29, 2026

California: Clean Truck Check Rules Still in Force for Out-of-State Trucks, Despite EPA Disapproval

The Environmental Protection Agency said California can’t enforce its Heavy-Duty Inspection and Maintenance Regulation, known as Clean Truck Check, on vehicles registered outside the state. But California said it will keep enforcing the rule.

Read More →
Ad Loading...
Illustration of Department of Justice building superimposed by truck exhaust stacks
Fuel SmartsJanuary 27, 2026

Justice Department Pulls Back on Criminal Prosecution of Diesel Emissions Deletes

The Trump administration has announced it will no longer criminally prosecute “diesel delete” cases of truck owners altering emissions systems in violation of EPA regulations. What does that mean for heavy-duty fleets?

Read More →