Lexus IS F 2012 Owner's Manual page 211

(6)If your vehicle will be towing a trailer, load from your trailer will be
transferred to your vehicle. Consult this manual to determine how this
reduces the available cargo and luggage load capacity of your vehi-
cle.
Lexus does not recommend towing a trailer with your vehicle. Your vehicle is
not designed for trailer towing.
Example on your vehicle
When 2 people with the combined weight of 366 lb. (166 kg) are riding
in your vehicle, which has a total load capacity of 660 lb. (300 kg), the
available amount of cargo and luggage load capacity will be as follows:
660 lb. — 366 lb. = 294 lb. (300 kg —166 kg = 134 kg)
In this condition, if 2 more passengers with the combined weight of 258 lb.
(176 kg) get on, the available cargo and luggage load will be reduced as fol-
lows:
294 lb. — 258 lb. = 36 lb. (134 kg — 117 kg = 17 kg)
As shown in the above example, if the number of occupants increases,
the cargo and luggage load will be reduced by an amount that equals the
increased weight due to the additional occupants. In other words, if an
increase in the number of occupants causes an excess of the total load
capacity (combined weight of occupants plus cargo and luggage load),
you must reduce the cargo and luggage on your vehicle.
2-5. Driving information
Cargo capacity
Total load capacity
2
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