Back in time, in a galaxy far, far away, when Holden Kingswoods, Ford Falcons, and Valiant Regals roamed the earth and were used as regular tow vehicles in Australia, towing specifications looked a little different to what they do today. In some cases, they were specified by the caravan manufacturers and usually only mentioned one thing — engine horsepower, and preferably V8 horsepower at that. Weights didn’t often get a mention and were you able to travel back in time and mention things like GVM, TBM, GCM and ATM, you’d received some very puzzled looks.
“Gross Combined Mass is specified by the tow vehicle manufacturer and is the maximum allowable mass of the tow vehicle and the caravan”
About a decade ago, one of those, Gross Combined Mass (GCM), only really concerned fifth-wheeler manufacturers and owners. It was essential because tow vehicle manufacturers didn’t
