 Produced as both a straight/rigid truck and a tractor, a wide range of versions of C-series was produced, ranging from Class 5 to Class 8 GVWR ratings.The C-series was also used as a basis for fire apparatus production.Produced for 33 years nearly unchanged (with the exception of its powertrain), the C-series was the longest-produced commercial truck in North America at the time of its withdrawal; only the Mack Model R (39 years) and Kenworth W900 (59 years; still in production) have remained in production longer.