COLUMBUS, Ind. — After agreeing to a global engine partnership with Cummins’ chief rival last week, Navistar International announced today it has also extended its engine supply agreement with the Columbus-based engine maker for Class 8 on-highway diesels through 2013.

The agreement is for the ongoing supply of Cummins ISL, ISM and ISX engines for use in Navistar’s International brand heavy-duty trucks. Cummins has already announced it will meet 2010 emissions standards without the use of SCR.

Beginning in 2010, Cummins will be Navistar’s exclusive supplier for 15- and 16-liter Cummins ISX big bore diesel engines for International trucks in North America.

This comes after last week’s news that Caterpillar, Navistar’s other longtime powertrain supplier, is leaving the heavy-duty on-highway truck engine business by 2010, before the next round of emissions legislation kicks in.

Cummins already supplied about 75 percent of Navistar’s big-bore engines.

Instead it will focus on "co-operating" with Navistar on engine platforms. The first product from the deal will reportedly be a Cat-branded heavy vocational truck that will hit the market in 2010. The agreement will also pursue opportunities in the construction, oilfield, and other severe-service on/off-road applications.