Cummins Inc. has produced its 2-millionth diesel engine for Ram Trucks.

The 350-horsepower, 6.7-liter, in-line 6-cylinder turbo diesel is distinguished by its "Cummins Red" rocker cover and breather. But despite its 800 pound-foot peak torque rating, the engine - feted recently at a Cummins plant in Columbus, Ind. - will not see service. Instead, it will go on display, touring the U.S.

Cummins began supplying engines to Chrysler Group in 1988. Today in North America, only Ram-brand pickups and chassis cabs feature the coveted Cummins "C" logo.

The Chrysler Group-Cummins partnership traces its beginnings to 1985, when development work began on a 5.9-liter 12-valve in-line 6-cylinder turbo diesel. When it launched in 1989, it was rated at 160 horsepower and 400 pound-feet of peak torque - less than half the numbers for today's High-Output 6.7-liter Cummins turbo diesel.

In the 2013 Ram Heavy Duty pickups, the Cummins engine makes 385 horsepower and 850 pounds-feet of torque.

Among other notable events in the evolution of Cummins diesels produced for Chrysler Group:

- 24-valve design introduced in model-year 1998.5
- Adoption of high-pressure common-rail fuel delivery in 2003
- Named to Ward's 10 Best Engines list in 2004
- Displacement increased to 6.7 liters from 5.9 liters in model-year 2007.5
- Met 2010 EPA emissions certification in 2007