MikeAqua:
Truck has always been used in NZ, instead of lorry (which seem to be a UK thing).
I agree that we used to refer to fire engines. I'm not sure when it changed to trucks.
When working in England in 1989, I had a colleague refer to these vehicles as a lorry when the semi-trailer was attached and as a truck when there was no semi-trailer. It surprised me to hear him call it a truck, and it seems to have stuck in my mind.

