What is DGVW or MAM? Design Gross Vehicle Weight (or Maximum Authorised Mass (MAM) is the weight of a vehicle (or trailer) including the maximum load it can carry according to the manufacturer’s design specifications.
What is DGCW or GTW? The Design Gross Combined Weight (DGCW) or Gross Train Weight (GTW) is the combined maximum allowable weight of the vehicle and trailer according to manufacturer’s specifications.
What is unladen weight? The weight of the vehicle when not carrying any passengers, goods or other items. In the case of a trailer, the unladen weight is the weight of the trailer itself with no load.
What can your vehicle tow? The towing capacity (or towable mass) is the maximum weight that a vehicle can tow according to the manufacturer’s specifications.
Where do I find out my vehicle’s towing capacity? Each vehicle is different and so is its towing capacity (i.e. what weight it can tow). There are three ways in which you can find out your vehicle’s towing capacity:
1. The Owner’s Manual
2. Contact the original manufacturer or authorised distributor, or
3. Calculate it from your vehicle’s plate (located either on inside passenger door or under bonnet).
Is my vehicle’s towing capacity the same for braked and unbraked trailers? No. The ‘Braked’ towing capacity is what the vehicle can tow with trailer brakes used. The ‘unbraked’ towing capacity only applies to trailers up to the legal maximum of 750kg. Trailers under this weight only need brakes if the weight of the trailer is more than half the weight of the towing vehicle.
Where do I find the braked and unbraked towing capacity for my vehicle? The figure calculated from your vehicle’s plate (as explained above) is for braked towing capacity only. To find out the unbraked towing capacity of your vehicle please refer to your owner’s manual or contact your vehicle’s manufacturer or authorised distributor.
Is it OK to tow a trailer that is heavier than my vehicle’s towing capacity if the trailer is unloaded? It’s OK to tow a trailer whose DGVW exceeds a vehicle’s towing capacity provided the combined weight of the trailer and the load being carried does not exceed the specified towing capacity of the drawing vehicle.
Where do I find the gross weight of my trailer? You will find the Design Gross Vehicle Weight (DGVW), or Maximum Authorised Mass (MAM), on the statutory plate fixed to your trailer or by contacting your trailer manufacturer or authorised distributor.
My trailer is homemade and has no plate. Where can I find its gross weight? You can try contacting an existing trailer manufacturer in your area and ask them if they will plate it for you.
Where can I weigh a trailer to find its weight? Please contact your local authority for a list of approved weighbridges in your area to get your trailer weighed.
Do all trailers need to be plated? Since 29 October 2012 all new light trailers must be plated.
What can I tow with a B (car) or BE Driving Licence?
B Licence A trailer whose Design Gross Vehicle Weight is not more than 750kg, or if the trailer’s Design Gross Vehicle Weight is more than 750kg but the Design Gross Combination Weight of the vehicle + trailer does not exceed 3,500kg
BE Licence A trailer whose Design Gross Vehicle Weight is not more than 3,500kg, or the trailer’s Design Gross Vehicle Weight is more than 750kg and less than 3,500kg but the Design Gross Combination Weight of the vehicle + trailer does not exceed 7,000kg.
More Information can be found on www.rsa.ie