Work Truck Logo
MenuMENU
SearchSEARCH

Johnson Matthey Technology Puts World’s Cleanest Class 8 Diesel Trucks on Southern California Roads

LONG BEACH, CA – Older big-rig trucks now can have cleaner emissions than even the most modern clean diesel trucks. Johnson Matthey’s latest diesel emissions technology, the SCRT system, was unveiled in Southern California recently at the “Future Is Green” conference.

by Staff
October 7, 2008
3 min to read


LONG BEACH, CA – Older big-rig trucks now can have cleaner emissions than even the most modern clean diesel trucks. Johnson Matthey’s latest diesel emissions technology, the SCRT system, was unveiled in Southern California recently at the “Future Is Green” conference, an annual gathering of the California Air Pollution Control Officers Association, made up of air pollution fighters from throughout California. The event is hosted by the South Coast Air Quality Management District.

Ad Loading...

Johnson Matthey announced that a demonstration of its advanced diesel retrofit technology has been launched with a fleet of 16 older trucks owned by the Ralph’s supermarket chain in Southern California. Johnson Matthey and its partner, Cummins Emissions Solutions, retrofitted 16 older Class 8 grocery trucks used in the Ralphs’ delivery fleet with the new SCRT four-way control system. The trucks range in age from 1998 to 2004.

Ad Loading...

The demonstration program involved a local partnership between Ralphs, the South Coast AQMD, and Johnson Matthey. Johnson Matthey will collect data on the vehicle’s emissions performance by measuring back pressure, temperature, and nitrogen oxides (NOx), a key smog-forming pollutant.

The four-way SCRT exhaust emission control system combines Johnson Matthey’s patented two-stage CRT particulate filter system (to reduce particulate matter by more than 85 percent) with a selective catalytic reduction (SCR) catalyst that reduces NOx by some 60 to 80 percent. It also reduces carbon monoxide (CO) and hydrocarbons (HC) by more than 90 percent. The result is a four-year-old truck with NOx emissions lower than those of a brand-new 2008 truck. The Ralphs trucks with this system could potentially remain in compliance with existing and proposed air quality regulations until 2020.

In a previous test using a similar fleet of grocery trucks in the Sacramento area, Johnson Matthey found that the SCRT system reduced NOx by an average of 84 percent compared to pre-retrofit levels. Those trucks had 2005 Cummins, 400-horsepower ISM engines with an EGR (exhaust gas recirculation) system. The ISM is a commonly used engine in Class 8 trucks hauling heavy loads.

At the “Future is Green” conference, Johnson Matthey also showed some of its technology being used on new vehicles, including a system used on the 2008 Dodge Ram pickup powered by a Cummins 6.7L turbodiesel that already meets emissions standards that take effect in 2010.

The next stage for this technology is verification by the California Air Resources Board and the U.S. Environmental Protection Agency, which is underway now. Johnson Matthey expects verification of the system by the end of 2008 or early 2009. The company has nearly 50 demonstration units running in California and Texas. After thousands of hours of operation, the SCRT system retrofits on both EGR and non-EGR engines has reduced NOx emissions by as much as 84 percent.

More Operations

Work Truck graphic calling for industry insights on 2026 trends and 2027 forecasts.
Operations•by Lauren Fletcher•October 29, 2026

Work Truck Seeks Fleet and Industry Insights on 2026 Trends and 2027 Forecasts

Work Truck is seeking insights from fleet leaders and industry partners on the trends that shaped 2026 and what commercial fleets should prepare for in 2027. Participate today!

Read More →
Bob Adamsky, director of fleet management at Arrow International, speaks into a microphone during a panel discussion at Work Truck Exchange, alongside fellow fleet industry professionals.
Operations•by Lauren Fletcher•October 29, 2026

30 Years in Fleet and Still Learning: Lessons Beyond Trucks

After more than three decades in fleet, Bob Adamsky has learned that knowing trucks is only part of the job. The bigger lessons come down to communication, understanding, and never assuming you know it all.

Read More →
Black-and-white portrait of Carolyn Edwards on a Legends of Fleet video thumbnail, presented by Work Truck and sponsored by Legend.
Sponsored•by Lauren Fletcher•October 29, 2026

What Every New Fleet Manager Should Know

Carolyn Edwards shares lessons on finding mentors, showing fleet’s value, and leading teams in this episode of Legends of Fleet.

Read More →
Ad Loading...
Flowers, balloons, stuffed animals, and glowing candles surround the Silver Rail Elementary School sign at a memorial in Bend, Oregon.
Operations•by Staff and News Reports•October 27, 2026

Les Schwab Tires Launches Foundation With $100,000 for Community Recovery

Les Schwab Tires launches a foundation with $100,000 to support recovery for Silver Rail Elementary and the Bend community following a school shooting.

Read More →
Side-by-side photos show pumpkin seeds being scooped out with a wooden spoon and a person carving a jack-o’-lantern with triangular eyes and a jagged smile.
Operations•by Lauren Fletcher•October 26, 2026

Bring Some Fleet to Your Halloween with Our Pumpkin Carving Templates

Download Work Truck’s truck-themed pumpkin patterns, explore more automotive designs, and give your shop or front porch a seasonal upgrade.

Read More →
Work Truck Trucks, Tips & Tours YouTube thumbnail featuring a WEX representative discussing the future of fleet fuel payments, with a WEX-branded backdrop, bold yellow and white headline, and Truck Chat Watch Now button.
Operations•by Wayne Parham•October 23, 2026

How Cardless Fuel Payments Benefit Commercial Fleets

Is it time for fleets to move beyond plastic fuel cards? David Abraham of WEX explains how cardless fuel payments can help reduce fraud, simplify driver transactions, and improve efficiency by allowing drivers to pay for fuel using their smartphones.

Read More →
Ad Loading...
Three overlapping sticky notes in Work Truck brand colors reading “Listen,” “Think,” and “Speak” sit on a worn automotive workbench surrounded by tools and hardware.
Operations•by Lauren Fletcher•October 23, 2026

Good Fleet Leadership Starts With the People You Already Have

From developing future leaders to listening to employees, discover how better leadership can help work truck fleets retain talent and build stronger teams.

Read More →
Work Truck leadership update graphic featuring Page Siplon, president and CEO of the American Transportation Research Institute (ATRI), with his portrait against a blue gradient background and the Work Truck logo.
Operations•by News/Media Release•October 21, 2026

ATRI Names Next President and CEO

Page Siplon, a longtime transportation and logistics industry executive, has been chosen as the next president and CEO of the American Transportation Research Institute (ATRI).

Read More →
Promotional graphic for Coltrain Onsite Fleet Care's sponsorship of the 2026 StaffDNA Cure Bowl, featuring two branded Ford service trucks, the Cure Bowl logo, and the message "Defend the Road. Defend the Cure" against a black, yellow, and pink background.
Operations•by Staff and News Reports•October 20, 2026

Coltrain Onsite Fleet Care Sponsors 2026 Cure Bowl to Support Cancer Research

The mobile fleet maintenance provider is supporting the annual college football bowl game, which has helped raise $6.83 million for cancer research since 2015.

Read More →
Ad Loading...
alt image text for accessibility Work Truck Weekly Cheat Sheet thumbnail featuring Lauren Fletcher, race car driver Isaac Johnson, a blue Republic Services electric refuse truck, and a Ghostbusters-themed Rivian SUV. Text highlights racing lessons, EV fleet growth, and Ghostbusters fun.
Operations•by Lauren Fletcher•October 19, 2026

Racing Lessons, Electric Fleet Growth, and Ghostbusters Lead This Week's Work Truck News

Racing lessons for fleets, Republic Services' electric truck expansion, 40 years of fleet wisdom, truck trivia, autonomous yard trucks, and more headline this week's Truck Chat Cheat Sheet.

Read More →