Toyota 2008 Prius Quick Reference Manual page 204

2-5. Driving information
(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 vehicle. (→P. 176)
Toyota 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 815 lb. (370
kg), the available amount of cargo and luggage load capacity will be
as follows:
810 lb. — 366 lb. = 444 lb. (365 kg — 166 kg = 199 kg)
In this condition, if 3 more passengers with the combined weight of
388 lb. (176 kg) get on, the available cargo and luggage load will be
reduced as follows:
444 lb. — 388 lb. = 56 lb. (199 kg — 176 kg = 23 kg)
As shown in the above example, if the number of occupants
increases, the cargo and luggage load equaling the combined weight
of the occupants who got on later, by an amount. 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.
174
PRIUS_U_(L/O_0802)
Cargo capacity
Total load capacity