Toyota 2012 Yaris Hatchback Owner's Manual page 160

Trailer tongue load
● A recommended tongue load varies in accordance with the types
of trailers or towing as described below.
● In order to ensure the recommended values shown below, the
trailer must be loaded by referring to the following instructions.
The trailer cargo load should be distributed so that the tongue load
is 9 to 11% of the gross trailer weight, not exceeding 70 lb. (31 kg).
(Tongue load / Gross trailer weight x 100 = 9 to 11%)
The gross trailer weight and tongue load can be measured with plat-
form scales found at a highway weighing station, building supply
company, trucking company, junk yard, etc.
Hitch
Trailer hitch assemblies have different weight capacities established
by the hitch manufacturer. Even though the vehicle may be rated for
towing a higher weight, the operator must never exceed the maxi-
mum weight rating specified for the trailer hitch.
Connecting trailer lights
Please consult your dealer when installing trailer lights, as incorrect
installation may cause damage to the vehicle's lights. Please take
care to comply with your state's laws when installing trailer lights.
2-5. Driving information
Gross trailer weight
Tongue load
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