Porsche Cayman Owner's Manual page 228

Tire life
Tire life depends on various factors, i.e., road
surfaces, traffic and weather conditions, driving
habits, type of tires and tire care.
f
Inspect your tires for wear and damage before
driving off. If you notice uneven or substantial
wear, wheels might need alignment or tires
should be balanced or replaced.
Tire wear
The original equipment tires on your Porsche have
built-in tire wear indicators. They are molded 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.
In the United States, state laws may govern the
minimum tread depth permissible. Follow all such
laws.
h
Excessively-worn tires
DANGER
Driving on worn tires can result in loss of control
of the vehicle and could cause serious personal
injuries or death.
f
Do not drive with worn tires or tires showing
cuts or bruises as they may lead to sudden
deflation and loss of control which could cause
severe personal injury.
226
Minor Repairs
f
Specialized high performance tires on high
performance sports cars exhibit more wear
than those on a family sedan, or even a high
performance sedan.
Therefore, it is important to check your tire
pressure and condition at least every two
weeks.
f
If you notice that tires are wearing unevenly,
consult your authorized 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.
Tire care
f
Avoid damaging tires and wheel rims.
f
If you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle.
f
Check tires for uneven wear and damage
before driving off.
f
Remove embedded material.
f
Replace worn or damaged tires immediately.
f
Keep oil, fuel, brake fluid, etc. away from tires.
f
Replace missing valve stem caps.
f
Keep tires inflated correctly.
f
Wash tires when washing the vehicle. Also
clean inner side of wheels.
f
Do not use abrasive cleaners when washing
the wheels.
f
Check wheel rims for corrosion.
f
Remove road salt, if driving in winter.
Tire damage, puncture
f
Please see the chapter "HIGH-PRESSURE
CLEANING EQUIPMENT, STEAM CLEANERS"
on page 211.
h
Damaged tire check
DANGER
Driving the vehicle with low tire pressure increases
risk of a tire failure and resulting loss of control.
Furthermore, low tire pressure increases the rate
of wear of the affected tires.
f
Check tires – including sidewalls – regularly for
foreign bodies, nicks, cuts, cracks and bulges.
f
After driving off road, examine tires for signs
of damage such as cuts, tears, bulges or
foreign objects stuck in the tread. Replace a
damaged tire if necessary.
f
Cross curb edges slowly and at right angles if
possible.
Avoid driving over steep or sharp curbs.
f
In cases of doubt, have the wheel (particularly
the inner side) checked by an authorized
Porsche dealer.
In case of tire damage, where it is uncertain
whether there is a break in the ply with all its
consequences or tire damage caused by thermal
or mechanical overloading due to loss of pressure
or any other prior damage, we recommend that
the tire be replaced for safety reasons.
If one faulty tire is replaced it should be noted that
the difference in tread depth on one axle must not
exceed 30%. Handling inconsistencies may result.
f
Recommendation: Replace both tires on one
axle so that no handling inconsistencies may
result due to different tread depths.
f
Perform a visual inspection if necessary.