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

Shades of Fleet “Family Ties” thumbnail with Lauren Fletcher, a family tree graphic, keys, and Work Truck branding.
Operationsby Lauren FletcherSeptember 15, 2026

Family Ties Inside the Fleet Families Building Careers Across Generations

Three fleet families share what it really takes to work together, learn across generations, and keep business from following them home.

Read More →
Shades of Fleet Hidden Heroes graphic featuring silhouetted dispatchers, coordinators, parts specialists, and support staff working across fleet operations, with a Share Your Story callout.
Operationsby Lauren FletcherSeptember 15, 2026

Shades of Fleet Call for Voices: Fleet's Hidden Heroes

Fleet’s hidden heroes are often the ones keeping everything moving behind the scenes. September’s Shades of Fleet is looking for dispatchers, coordinators, parts specialists, and other support pros to share their stories.

Read More →
Truck Centers Inc. graphic recognizing National Truck Driver Appreciation Week, Sept. 14–18, over an image of a semi-truck traveling along a rural highway beneath a cloudy sky.
Operationsby News/Media ReleaseSeptember 14, 2026

Truck Centers, Inc. Celebrates National Truck Driver Appreciation Week with $1,000 Fuel Card Giveaways

During National Truck Driver Appreciation Week, Truck Centers, Inc. is offering customers a chance to fuel up for free. Customers at all Truck Centers locations can enter to win one of four $1,000 fuel cards from Sept. 14 - 18.

Read More →
Ad Loading...
Lauren Fletcher appears in a Work Truck Weekly Truck Chat Cheat Sheet thumbnail with bold blue, black, white, and orange graphics. Text highlights fleet guides, AI, tariffs, and fuel strategy, with a semi-truck in the background.
Operationsby Lauren FletcherSeptember 14, 2026

Fleet Guides, AI Time-Savers, Truck Tariffs & Fuel Strategy Lead the News

This week’s Truck Chat Cheat Sheet covers new fleet vehicle guides, practical AI use cases, U.S.-Canada truck production, mixed-energy strategy, and more.

Read More →
Podcast cover for “The Fleet Skills We Keep Missing on Veterans’ Resumes” featuring a folded American flag, military dog tags, a resume listing leadership and adaptability skills, a wrench, and vehicle keys on a dark workbench.
OperationsSeptember 11, 2026

What Fleet Employers Are Missing When Hiring Veterans

What if some of the strongest candidates for fleet are already out there, but their experience is written in a language our industry does not always recognize?

Read More →
Graphic promoting Automotive Fleet's 2026 Personal Use Survey with the text "Have a Personal Use Policy? We Want to Know!" encouraging fleet managers to complete the annual industry survey.
Operationsby StaffSeptember 8, 2026

Automotive Fleet Opens 2026 Personal Use Survey for Commercial Fleet Managers

Less than two weeks left! Commercial and corporate fleet managers are invited to share how their organizations handle company vehicle personal-use policies, charges, and driver eligibility.

Read More →
Ad Loading...
Truck Chat promotional graphic featuring two hosts and the headline “Operate Fleet at the Speed of Business,” presented by Work Truck.
Operationsby Lauren FletcherSeptember 7, 2026

What Resilient Fleets Do Differently When Conditions Change

Fleet resilience is about more than reacting to disruption. Lauren Fletcher talks with AP Fleet’s Alex Coveney about flexibility, planning, scaling, and what helps fleets adapt when business conditions shift.

Read More →
View down the 996-foot Soap Box Derby track at Derby Downs in Akron, Ohio, with grandstands, the starting structure, and a colorful Soap Box Derby sign in the foreground.
Operationsby Lauren FletcherSeptember 1, 2026

If We Want the Next Generation in Automotive, We Have to Give Them a Reason to Care

The automotive industry talks constantly about its workforce shortage. But before we can recruit the next generation, we may need to do a better job giving kids a reason to care about automotive in the first place.

Read More →
Work Truck Weekly Truck Chat Cheat Sheet thumbnail featuring Lauren Fletcher with blue hair and raised hands beside a work truck, with callouts for Ram under $40K, tariffs, and AI maintenance.
Operationsby Lauren FletcherAugust 31, 2026

Ram ProMaster City Under $40K, Truck Tariffs, and AI Maintenance Lead the News

A sub-$40K commercial van, tariff questions, AI-powered maintenance, and a new EV production strategy headline this week’s Truck Chat Cheat Sheet.

Read More →
Ad Loading...
Fleet Legends promotional graphic featuring Bob Adamsky in a suit beside bold black, white, and yellow text reading “Legends of Fleet,” with his name and the tagline “Decades of Leadership. Lessons That Last.”
Sponsoredby Lauren FletcherAugust 31, 2026

Bob Adamsky Shares the Fleet Lessons You Usually Learn the Hard Way

After more than 30 years in fleet, Arrow International’s Bob Adamsky has learned that the job is about far more than vehicles. He shares the lessons he wishes every fleet manager could learn a little earlier.

Read More →