TOOELE, UT. Following the announcement that Navistar will be switching to SCR technology to meet 2010 EPA emissions regulations of 0.2 grams of NOx, the only question left unanswered is when?

Some of that answer came when the company announced it would begin offering the Cummins ISX 15 in January in select models and would have a MaxxForce 13L engine with SCR available early next year. Tim Shick, vice president-- North American engine sales, and Jim Hebe, executive vice president-- North American sales, further clarified that timeline yesterday during a media session as part of the Navistar Vocational Boot Camp for dealers here at the Miller Motorsports Park.

According to Hebe, the timeline for implementing MaxxForce EPA-certified engines into the product range is as follows:

·         MaxxForce 11L: April 2013

·         MaxxForce 13L: April 2013

·         MaxxForce 9L, 10L and DT engines: January 2014

·         MaxxForce 7: January 2015

In addition, early versions of the Cummins ISX 15 are currently being prepared for the ProStar + at this time with full rollout due in January. This engine will be added to the 9900 in April 2013 and the 5900 SBA in May of 2013.

Cummins ISL G natural gas engines will be available in the TranStar in January 2013 and in the new LoadStar when it debuts in July 2013.

Credits and nonconformance penalties will be used until the new engines are available.

Shick said there is an expected fuel economy gain with the addition of Cummins SCR aftertreatment to the MaxxForce engines as well as improved throttle response on the MaxxForce 13.

“There is a weight gain, there’s no way around it, but we’re still going to be the lightest long-haul tractor out there,” Shick added. He said the SCR components will add about 400 lbs. to the vehicles.

Mark Karrasch, division manager-South Central region for Cummins, said the fuel economy gain on a 2013 Cummins ISX 15 engine is about 2% and it is available in ratings from 400-450 hp. with 1,750 lbs.-ft. of torque, 455-500 hp. with 1,850 lbs.-ft. of torque, and 525-600 hp. with 2,050 lbs.-ft. of torque.

He said additional ratings will be available for Navistar..