How is GCM different from GVM and towing capacity?

GVM is the maximum loaded weight of the vehicle on its own. Towing capacity is the maximum weight of the trailer you're allowed to tow. GCM is the maximum combined weight of vehicle and trailer together. You can hit the tow rating but breach GCM if both the vehicle and caravan are heavily loaded.

Where do I find the GCM for my vehicle?

GCM is usually listed in the owner's manual, specification guide or on a compliance plate. Not all older vehicles list GCM clearly, and some manufacturers only specify GVM and tow limits. If you can't find it, check your manufacturer's documentation or contact the dealer for confirmation.

GCM upgrades are more complex than GVM upgrades and may not be permitted in every state or for every vehicle. Some engineering packages may advertise increases, but regulations vary widely, and insurance acceptance can differ. Always speak with a qualified engineer and your insurer before assuming any GCM increase is valid.

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GCM Calculator – Check Your Gross Combination Mass With Caravan On

Use this GCM calculator to see the total weight of your tow vehicle and caravan combined and compare it to the manufacturer's Gross Combination Mass (GCM) limit. Enter your vehicle, caravan and load details to get a clearer picture of whether your full setup is within legal limits – not just your towing capacity.