Detroit Diesel Corp. has received EPA certification for its 12.7- and 14.0-liter Series 60 on-highway engines. The Series 60 engine is ... two different families of the Series 50 urban bus engines ...

As a result, Detroit Allison built their first four-stroke engine in 1989, known as the Series 60. In the years following its release, the Series 60 became the best-selling four-stroke commercial ...