VM Motori history
Detroit Diesel Corporation
(DDC) bought VM Motori in 1995.
In 2000 the DDC was purchased by DaimlerChrysler
In 2003, Penske Corporation
purchased a 51% stake in VM Motori; in 2007, Penske bought the remaining 49% from DaimlerChrysler and subsequently sold 50% of it to General Motors.
 As of 2007, both deals were awaiting European regulatory approval and the value of the deal was not known.
In September 2008, GAZ Group announced plans to purchase a 50% stake from Penske Corp. but ultimately cancelled them in February 2009. January 11, 2011 Italian newspaper Corriere della Sera published news that Fiat S.p.A. is about to purchase 50% stake from Penske. In February 11 Fiat Powertrain Technologies
confirmed it has bought the 50 percent stake.
The agreement between Chrysler & Cummins that you mentioned, was ONLY for a diesel engine for the 1500s
It didn't have anything to do with the diesel engines in the Larger Rams