Porsche Boxster Owner's Manual page 257

Determining the combined weight of occupants
and cargo:
Add the weight of all occupants and then add
the total luggage weight (gure).
Steps for determining correct load limit
1. Locate the statement "The combined weight of
occupants and cargo should never exceed XXX
pounds" on your vehicle's placard (depending
on the date of manufacture).
2. Determine the combined weight of the driver
and passenger that will be riding in your
vehicle.
3. Subtract the combined weight of the driver and
passenger from XXX kilograms or XXX pounds.
4. The resulting figure equals the available
amount of cargo and luggage load capacity.
For example, if the "XXX" amount equals 400
lbs. and there will be two - 150 lb passengers
in your vehicle, the amount of available cargo
and luggage load capacity is 100 lbs. (400 -
300 (2 x 150) = 100 lbs.).
5. Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated in
Step 4.
Practical Tips, Emergency Service
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