RV FEATURE
MAXIMUM TOWBALL DOWNLOAD
Maximum Towball Download is the maximum amount of weight that a trailer can transfer onto the tow vehicle . Again , it should be stated either in the vehicle user manual or on the tow hitch itself . What is not well understood is this towball weight must be added into your calculations when assessing the total weight of your vehicle against its GVM . When the drawbar of a trailer rests on the towball , that weight is carried by the tow vehicle .
Note : Maximum Towball Download is a rating that must not be exceeded .
GROSS COMBINED MASS
The Gross Combined Mass of a tow vehicle is the value specified for the vehicle by the manufacturer as being the maximum of the sum of the Gross Vehicle Mass of the tow vehicle plus the sum of the ‘ axle loads ’ of any vehicle capable of being drawn by the tow vehicle as a trailer . If a complete rig is put on a weighbridge , the total weight of the rig cannot exceed the GCM .
Finding out the GCM of your particular tow vehicle can be difficult . Some manufacturers state the GCM on the compliance plate but many do not . Some manufacturers , meanwhile , state the GCM as simply the sum of the
maximum towing capacity and the GVM . Some state a GCM for their vehicle on their website or in the vehicle ' s user manual . It can also change depending on the year the vehicle was manufactured .
If the vehicle has had a GVM upgrade , the GCM may or may not have been increased as well . The second stage manufacturer ' s compliance plate may not state a GCM , either , adding more confusion .
If you have the slightest doubt about your vehicle ' s GCM , you must consult the manufacturer of the vehicle and / or the manufacturer of the GVM upgrade , if one has been fitted .
It is vitally important to ascertain these ratings on your tow vehicle if you are to ensure you remain legal . If , after consulting the manufacturer , you still have doubt , visit your state road authority . It will have up-to-date information about your vehicle and can help make sense of what is stated on the compliance plate .
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