The VWLs Galway have are equipped with a ZF 6HP592 gearbox i.e. one with six gears. In fact all the 07/08 reg ones have a six speed gearbox. The other VWLs have four speed ZF gearboxes.

Sixth gear is only engaged above about 60 km/h - which is too high on a city service, but in Cork and Waterford, where they are used on local services as well, the sixth gear is there and is needed.

The VWDs have ZF Ecolife gearboxes - and I am quite sure that the Ecolife is now available on the Volvo B7RLE chassis too. This is also a six speed gearbox.

ZF unveiled an eight speed gearbox about three years ago and last month they revealed a nine speed gearbox for cars, it will be interesting to see will ZF make an eight speed gearbox for buses as well. An eight speed gearbox will allow the engine to run at lower revs at higher speeds, which saves fuel. The eight speed gearbox in cars has an auto stop and start function, such a feature could massively reduce fuel consumption on citybuses without the cost or complexity of hybrid technology.