Navistar International Corporation reported it has started shipping its International ProStar+ Class 8 trucks, powered by the Cummins ISX15 engine. The OEM announced 300 International ProStar+ Class 8 on-highway tractors equipped with the Cummins ISX15 had been delivered to buyers.

Navistar builds trucks and other commercial vehicles, and it manufacturers diesel engines for its own products and for other automotive, commercial vehicle, and off-road equipment builders.

In August, Navistar outlined a plan to switch to the EPA-approved “selective catalytic reduction” (SCR) process available in Cummins Class-8 truck engines, and also to source some engines from Cummins for certain of its truck models. Those are the Cummins engines now installed in the International ProStar+ tractors Navistar is delivering to truck buyers.

International ProStar+ trucks, with Navistar’s reconceived MaxxForce 13 featuring the SCR-based after-treatment system, is on-track for pilot production in March 2013. Regular production is set to begin in April 2013.

Navistar’s remaining heavy-duty truck models will transition to SCR-based engine technology in phases throughout 2013, according to volume and customer demand.

As originally detailed in August, Navistar trucks with the Cummins ISX15 engine were scheduled for delivery in January 2013. Reaching the 'OK-to-Ship' milestone ahead of schedule has "demonstrates the tremendous progress we're making in delivering our first SCR-based Class 8 trucks to the marketplace," according to Troy Clarke, Navistar president and COO. "Working collaboratively and fully integrated with our Cummins colleagues, the team has beat an aggressive launch timeline while ensuring the highest levels of quality." Clarke said.

Since it announced its shift to the SCR-based emissions control technology, Navistar noted it has completed extensive tests and analyses of the process in its own and at customers’ field test units. Those tests included “hundreds of thousands of driving miles in real-world conditions,” the engine and truck builder stated.

Working collaboratively, Navistar said that together with its partner Cummins it has been focused on executing a smooth launch of the new truck/engine arrangement.