Porsche 928 1982 Owner's Manual page 68

Tires, Wheels
The original equipment tires on your Porsche
comply with all applicable Federal Motor Ve-
hicle Safety Standards.
Tire pressures
For good car handling and long tire service
life, it is important to maintain recommended
tire pressures. Tires which are inflated above
or below specifications can cause increased
tire wear, high gas consumption and affect
road holding of the car.
In the interest of safety, check the tire pres-
sure of all tires at least once a week, and al-
ways before going on a long trip.
Always use tire pressure gauge when
checking inflation pressures. Do not ex-
ceed the maximum tire inflation pressure
listed on the tire sidewalk (Also refer to
"Technical data"). Cold tire inflation pres-
sure means: when a car has not been dri-
ven for at least 3 hours or less than 1 mile.
Never let any air out of warm tires to meet
cold tire pressure specifications.
66
Wheel balancing
A wheel should always be balanced after a
tire repair. Even with regular use a wheel can
get out of balance, and should therefore be
balanced from time to time. Unbalanced
wheels may affect car handling and tire life.
When balancing light alloy wheels, use only
adhesive balancing weights supplied through
the Porsche parts service.
Tire life and rotation
Tire life depends on various factors, i.e., roads,
traffic and weather conditions, driving habits,
type of tires and tire care.
Inspect your tires at least every 2000 miles or
3000 km for wear and damage. If you notice
uneven or substantial wear, wheels might
need alignment or tires should be balanced or
replaced when necessary.
Porsche recommends rotation every 3000
miles or 5000 km. Rotation and balancing, al-
though an expense to you, will prolong tire life.
Tires must always remain on same side of
vehicle.
After rotation, adjust tire pressure and torque
wheel nuts diagonally to 94 ft lb (130 Nm). See
"Changing wheels".
Tire wear
The original equipment tires on your Porsche
have built-in wear indicators. They are mold-
ed into the bottom of the tread grooves and
will appear as approximately 1/2 in (12 mm)
bands when the tire tread depth is down to 1/16
of an in (1.6 mm).
When the indicators appear in two or more
adjacent grooves, it is time to replace the tires.
We recommend, however, that you do not let
the tires wear down to this extent. Worn tires
cannot grip the road surface properly, and are
even less effective on wet roads.
Do not drive with worn tires or tires show-
ing cuts or bruises as they may lead to
sudden deflation.
If you notice that tires are wearing unevenly,
consult your Porsche dealer. Uneven wear
may not always be due to improper wheel
alignment. It can be the result of individual
driving habits such as cornering at high
speeds. If the tire pressure is not checked and
adjusted regularly, abnormal tire wear can
also occur.