I should think the 5th series are like the K230UB or K310UD.
*Engine position**Engine Horsepower**Type of chassis* , instead of
*Engine Position**Generation/Series**Type of chassis*
So type of chassis is like UB for citybus, UD for city bus DD,
IB for intercity buses, UA for articulated city buses, EB for
coaches and so on.
When did the change took effect?
