1987 PORSCHE 944 tire size

The brake warning light on the dashboard will go out after the engine is started and the
parking brake is fully released.
WARNING
Release the parking brake fully. A partially engaged brake will overheat the rear
brakes, reduce their effectiveness and
cause excessive wear.
Always set the parking brake when parking your car. Move the selector lever
to "P" (Automatic transmission) or move
the gearshift lever to reverse or first gear
(Manual transmission). On hills also turn
the wheels toward the curb.

WARNING Failure of one brake circuit will impair the
braking capability resulting in an
increased stopping distance.
If one brake circuit has failed, the other will
still operate. However, you will notice an
increased pedal travel when you step on the
brake. Should you encounter such
experience, bring your vehicle safely to a full
stop.
Avoid driving the vehicle and instead have it towed to the nearest authorized Porsche
dealer.

Brake Pedal

Parking Brake Lever
Parking brake force is mechanically trans-
ferred to the rear wheels by means of cables.
Use the parking brake only after the vehicle
has come to a full stop.
To set parking brake,
pull the lever all the way up (arrow). With the ignition on, the brake warning light will come
on.
To release the parking brake,
pull the lever slightly up as you depress the
release button, and then push the lever all
the way down.

Brakes

Functioning of brake system
Your Porsche is equipped with a power
assisted hydraulic dual circuit brake system
with disc brakes at the front and at the rear. Both circuits function independently. One
brake circuit operates the front and the other
the rear axle.
In the unlikely event of hydraulic failure of
one circuit, push the brake pedal down
firmly and hold it in that position. A
mechanical linkage activates the second
circuit, and you will be able to bring the
vehicle to a stop.
WARNING
The movement of the brake pedal must never be obstructed by a floor mat or any
other object. In case one of the two brake
circuits fails, increased pedal travel is
required to bring your vehicle to a full
stop.

Make sure that the size of your floor mat does not hamper the movements of either brake, clutch or accelerator pedals in any
way.
Secure the floor mat against sliding into positions that could interfere with the
safe operation of your vehicle.
Do not "ride the brakes" by resting your foot on the pedal when not intending to
brake. Overheating and premature wear
of the brakes will result.
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Before descending a steep grade, reduce
speed and shift transmission into a lower
gear or driving position to control speed. Do
not ride the brakes or hold pedal down too
long or too often. This could cause the
brakes to get hot and not function properly.

Brake operation and brake warning light
Make it a habit to check the operation of your
brakes before driving. The failure of a brake
circuit is indicated by the lighting up of the
dual-circuit brake indicator lamp. See also
brake fluid warning lamp.
With correctly adjusted brakes the pedal travel to the point of brake actuation should be
13/16" to 19/16" (30 to 40 mm). Whenever the brake pedal travel is greater, have the brake
system checked.
Keep in mind that the braking distance
increases very rapidly as the speed increases. At 60 mph/100 km/h, for example, it is not twice but four times longer than at 30 mph/ 50
km/h. Tire traction is also less effective when
the roads are wet and slippery. Therefore,
keep a safe distance from the car in front of
you.

Brake Booster The brake booster assists braking only
when the engine is running. When the car is moving while the engine is not running, or if
the brake booster is defective, more pressure
on the brake pedal is required to bring the car
to a halt.
Moisture or road salt on brakes affects
braking
WARNING
Driving through water may reduce tire
traction. Moisture on brakes from road
water, car wash, or coating of road salt
may affect braking efficiency. Cautiously
apply brakes to test them after being
exposed to such conditions. When the
vehicle is driven on salted roads for
extended periods, the brakes should be
hosed down thoroughly about every 2
weeks. An automatic car-wash facility
cannot do this job properly. Brakes will dry after a few cautious brake applications.
Brake wear
Our automobiles have excellent brakes, but
they are still subject to wear, depending on
how the brakes are used. Have the brake
system inspected at the intervals
recommended in your Warranty &
Maintenance booklet.

New brake pads or linings Brake pads or
linings may not have the highest possible
braking efficiency when new. Therefore allow
for longer braking distance during the initial
100 to 150 miles or 150 to 250 kilometers of
normal city driving; longer if fewer stops are
realized.
Clutch Pedal
Due to the hydraulic operation of the clutch,
pedal play should be 0.1" or 2.5 mm.
To check the play, depress the clutch pedal.
Excessive play or tightness indicate a
malfunction of the clutch. Both conditions can
lead to severe damage. Contact your Po
rsche dealer promptly to have the cause located and corrected. Always depress the clutch pedal fully when changing gears. Do not hold the car on a
steep hill with the clutch pedal partially
depressed. This will cause premature wear or
damage.

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ABS Brake System (Antilock brake system)
The ABS system represents a major
contribution to the enhancement of active
safety in your vehicle. This system prevents
the wheels from locking in a panic stop on
almost all road surfaces.
With ABS system in your vehicle, the
following areas are enhanced:
Full steerability , vehicle remains steerable
under all braking forces.
Good directional control , no swerving
caused by locking of wheels under braking
conditions.
Excellent stopping distance , stopping
distances are usually reduced because
controlled braking is maximized.
Prevention of wheel lock up , no brake-
induced sliding and thus no localized tire wear from emergency braking.
The crucial advantage of ABS system over a
conventional brake system is in the area of
maintaining directional control and
maneuverability of the car in emergency
situations, including panic braking in turns.
WARNING:
In spite of the improved handling afforded
by the ABS system, it still remains the
responsibility of the driver to adapt the
driving style to the prevailing road and
weather conditions, as well as, obeying
traffic laws. In no case, should the higher
degree of safety offered by ABS be
regarded as a

justification for taking greater risks. Other vehicles not equipped with the ABS
system may not be able to maintain
control, especially on wet or poor road
surfaces and thus may be more likely to
impact you in the rear. To minimize that r
isk, use your ABS system to increase your ability to maneuver to avoid dangerous
situations and not merely to try to stop in
the shortest distance possible.
Driving with the ABS System
A wheel speed sensor is fitted to each of the four wheels. If wheel slippage of either of the
front wheels or the rear wheels is sensed
during braking, the brake pressure is adjusted
automatically until the wheel no longer slips.
The brake pressure is regulated for each front
wheel individually and for both rear wheels together.
On a road surface which is slippery on only
one side, the rear wheel which is braking on
the slippery surface determines the brake
pressure which will be applied equally to both
rear wheels. This ensures that directional
stability is maintained. However, if braking
force approaches the wheel locking-up point
for all wheels (panic braking) the ABS system
will intervene in a way comparable with rapid rhythmic braking. The proper operation of ABS is perceived by the driver as a pulsating brake pedal in conjunction with audible noise
and perhaps some vibration. The driver is
thereby warned to reduce vehicle speed
appropriate for the prevailing road conditions.

If your ABS system should ever malfunction,
the ABS system is automatically switched off,
but the normal brake system, without ABS,
would remain fully operational. Such a malfunction would be indicated by the illumination of the central warning light, as well as the "ANTILOCK" light on the right hand
side of the instrument cluster.
If the ABS system becomes inoperative,
take your vehicle to your authorized dealer immediately.
Note
The control unit of the ABS brake system is
set for standard tire sizes. If non-standard
tires are fitted, the control unit may
misinterpret the speed of the vehicle, because of the variant data it receives from the sensors on the axles.
If the difference in rolling radius exceeds
approx. 17%, the control unit deactivates the
ABS system and the ABS warning lamp lights up.
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1 Set accelerate
2 Reset
3 Cancel

Automatic Speed Control
The automatic speed control allows you to
maintain a constant cruising speed of 25 mph
(40 km/h) or higher, without actuating the
accelerator pedal. Any manual operation,
such as accelerating, gearshifting or braking
can be done independent of the automatic
speed control. The spring loaded control lever
operating the automatic speed control is
located just below the wiper/ washer lever.
While driving with the automatic speed
control set at speeds above 25 mph (40
km/ h), do not bring shift lever into the
Neutral position as excessive engine rpm
will result.
To operate the automatic speed control Accelerate to the desired cruising speed, push lever toward instrument cluster (arrow 1) and
release. This sets the cruising speed and
stores it in a memory.
After a second or two, automatic speed control will take over and you can remove
your foot from the accelerator pedal. The set
cruising speed will be maintained
automatically.
WARNING
Do not use the cruise control when it may
be unsafe to keep the car at a constant
speed. For example, a constant speed may not be safe in heavy traffic, or on winding
or slippery roads. With the cruise control
system engaged, the engine speed will not
return to idle when removing the foot from
the accelerator pedal.
Please observe all local and national speed limits.

Passing: If you want to drive faster for a brief
moment, for example when passing another
vehicle, actuate the accelerator. When you
take your foot off the accelerator pedal, the
preset speed will automatically be resumed.
Gearshifting: When shifting gears, the
automatic speed control is only disengag
ed as long as the clutch pedal is depressed. The
preset speed will be resumed as soon as you
take your foot off the clutch pedal.
Braking and stopping: Whenever you apply
the brake or come to a stop, the automatic
speed control is disengaged. Move the lever
down (arrow 2), and the preset speed will be
resumed.

Switching system off: To switch off the
automatic speed control, move the lever
toward you (arrow 3). To resume the preset
speed, move the lever down (arrow 2).
To change the preset cruising speed
Increase preset speed:
Accelerate by depressing the accelerator pedal. When the desired speed is reached push lever toward instrument cluster (arrow 1) and take your foot off the accelerator pedal.
Now the new cruising speed is set and stored
in the memory. As an alternative, you can hold the lever in the front position (arrow 1), without depressing the accelerator pedal. The car will
accelerate on its own. When the desired
speed is reached, release the lever.
Decrease preset speed:
Apply the brake, which will disengage the automatic speed control. When the vehicle
has slowed down to the desired speed, push
lever toward instrument cluster (arrow 1) to
set the new cruising speed.
As an alternative, disengage the automatic
speed control by moving the lever toward you
(arrow 3). When the vehicle has slowed down
to the desired speed, push lever toward
instrument cluster (arrow 1) to register the
new cruising speed in the memory.
Note: When driving up a hill, if the engine
power is insufficient in a particular gear, the
speed control will be disengaged
automatically. Shift to a lower gear to avoid
stalling the engine.

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Tar or oil
Do not allow tar or oil to remain on the paint.
Remove as soon as possible with a cloth
soaked with a special paint cleaner. If you do
not have a tar or oil remover, you may
substitute with turpentine. After applying a
cleaning fluid, always wash with a lukewarm
soap water solution and apply a new wax
coat.
Insects
Remove as soon as possible with a lukewarm
soap/water solution or apply insect remover.
Tree sap Remove with a lukewarm soap/water solution. Do not allow tree sap or bird droppings to
harden on the paint.
Windows
Keep silicone sprays off the windshield to
avoid wiper smear in rain.
Generally, highway dust that settles on the
outside of the windshield contains material
worn from tires and oil residues. On the inside surfaces of the windshields, particularly in
strong sunlight, there are build-ups of dust
from the interior decor. These buildups are
reinforced by pollution in the air

brought in with the fresh air supply. Use a
lukewarm soap/water solution or an alcohol
based commercial window cleaning agent for t
he inside and outside. If a chamois is used for polishing the glass, it should exclusively be
used for that purpose.
To assure that windshield washers also
function at freezing temperatures, antifreeze
must be added to the washer fluids reservoirs
beforehand. It is advisable to use window
washer solvent with anti-freeze all year round. Follow directions on the can for the right
amounts to be used. Do not use engine
coolant anti-freeze or any other solution
that can damage the paint.
In vehicles with Sekurif
lex windshields, the plastic coating on the inside of the
windshield must not have gummed labels
put on it or be cleaned using abrasive
agents or dry methods. If very dirty, it can
be cleaned with benzine. The use of
benzine in a confined environment may be
dangerous to your health. Make certain
that the plastic coating is not damaged in
cleaning by hard objects such as jewelry
or wristwatches.
Do not remove ice on the inside of the
windshield by any means except warm air
from the defroster nozzles. Do not use any
deicer sprays, scratching tools, or
scrapers!

A foil base must be applied to the windshield prior to application of any labels or stickers
such as those used for state registration or
inspections. Failure to utilize foil base
between sticker or label and the Sekuriflex
coating will result in damage to the Sekuriflex
coating. Three foil bases were included with
the vehicle and additional foil bases may be
ordered from any Porsche dealer.
Instructions:
1. Clean the windshield in the area for
application.
2.
Cut the base of the foil to the required size.
Round off the edges.
3.
Pull off the protective film.
4. Spray the gummed side of the foil base and the windshield with a soap solution (distilled water and liquid soap or grease-free
detergent in a mixing ratio 10:1).
5.
Apply the foil base to the windshield and spray it once again.
6. Any liquid and bubbles under the foil base must be brushed out using a flexible plastic
scraper.
7.
Dry the windshield using a soft cloth.
8. Install label/sticker on the foil base.
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When removing the label/sticker or the
backing foil, first spray the foil with a soapy
solution (see point 4).
Wiper blades
Always loosen frozen wiper blades from glass as they may tear otherwise.
Remove all wiper blades periodically and
clean them thoroughly with an alcohol base
cleaning solution. Use a sponge or soft cloth
and wipe lengthwise.
Weatherstrips
To seal properly, weatherstrips around hood,
hatch, windows, doors, etc., must be pliable.
Spray with silicone or coat with talcum powder or glycerin to retain flexibility of the rubber and to protect against freezing in the winter.
Light alloy wheels
To preserve the decorative appearance of the
light aluminium castings, some special care is
necessary. Aside from road dirt and salt
sprays, brake metal dust will exert corrosive
effects.
If left on too long, brake metal dust can cause
pitting. Wash the wheels with a sponge or
hose brush every other week.

Roads salts should be removed weekly with
an acid free cleaning solution.
The acid free cleaning solution must not have
a pH value greater than 10 (see explanation),
in case of doubt, it is recommended to check
with the manufacturer of that particular cleaner.
Every three months (after regular cleaning)
the wheels should be coated with petroleum
jelly. Rub it in firmly with a soft cloth. Never use abrasive or metal polishing cleaning
agents.
Explanation of pH value
The pH value is a measurement for the
hydrogen-ion concentration in a liquid. This
value tells if the liquid reaction is sour (acid) o r alkaline (lye solution). At a pH value of 7, the reaction of the liquid is
neutral (that is, chemically clean water), it is
not an acid or alkaline. Acids have a pH value
under 7, the strength of the acid increases
with a lower pH value. Alkaline lies between a pH value of 7 and 14, the strength of the
alkaline increases with higher pH values.

For example: a mineral water mixed with
carbon dioxide has a pH value of 6-6.5,
reaction is also light sour. Battery acid in
comparison has a pH value of 1.
or
the pH value for normal soap solution is 8-9,
but the soap solution for a dishwasher is
approximately 12.5, this would not be suitable
for wheel cleaning.
Your Porsche dealer can advise you which
product to use.
Remember that moisture and road salt on
brakes may affect braking efficiency. Test
the brakes after each car or wheel wash.


64

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
WARNING
Avoid damaging tires and wheel rims. If you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle.
Frequently check tires for uneven wear and
damage.
Remove imbedded material. Replace worn or damaged tires immediately. Replace missing valve dust caps. Keep oil, fuel, brake fluid, etc. away from
tires.
Keep tires inflated correctly.

Tire replacement
In the interest of maximum safety and best
all-around car handling, always buy
replacement tires that have the same
specifications with regard to tire size,
design, load carrying capacity, tread
pattern, tread depth etc. This also applies
to Porsche recommended alternate
replacement tires. If you do not use a
Porsche recommended replacement tire,
make sure that you purchase your new
tires from a reputable

tire specially dealer and that the dealer complies with all manufacturers warnings
for those tires.
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 a
loss of pressure or any other prior damage,
we recommend that the tire be replaced for safety reasons.
If one faulty tire on an axle is replaced it
should be noted that the difference in tread
depth on one axle must not be more than
30%.
Tire specifications are imprinted on the
sidewall of the tires. If in doubt, check with
your Porsche dealer.
When replacing tubeless tires, always install
new valve stems. When replacing tires
requiring an inner tube, always install new
tubes.
New tires do not possess maximum
traction. They tend to be slippery. Break
new tires in by driving at moderate speed
for the first 60-120 miles or 100-200
kilometers.
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.

Wheels
If you intend to use other than original
equipment wheels, be sure that they conform
to Porsche specifications for your model.
Check with your Porsche dealer regarding the
correct wheel specifications for type and
model year.
Removing and storing tires
The driving direction should be clearly marked on all tires before removing them for storage,
to make sure they are mounted and run in the
same direction as before. Store tires in a cool
and dry place. Tires without rims upright!
Avoid contact with oil, grease or gasoline. When remounting, put tires with the most
tread depth at the front.
Snow tires
For a better grip on snow and ice use radial M + S tires or snow tires with studs. Check with
your local Motor Vehicle Bureau for possible
restrictions.
Radial ply M+S tires should be inflated with
the same cold tire inflation pressures required
for the regular radial ply tires. However, do not exceed the maximum tire inflation pressure
listed on the tire sidewall.
Snow tires should have the same load
capacity as original equipment tires and
should be mounted on all four wheels. Snow
tires with studs should be run at moderate
speeds when new in order to give the studs
time to settle.

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WARNING
Tires with badly worn treads and studs are
very dangerous. Make sure they are replaced
immediately.
Do not drive a vehicle equipped with snow
tires at prolonged high speed. Snow tires do
not have the same degree of traction on dry,
wet or snow free roads as a normal tire. Furthermore, snow tires wear rapidly under
these conditions.
Snow tires do not fulfill their purpose if the
tread depth is less than 5/32 in. / 4 mm.
Comply with all state and local laws
governing snow tire and tread depth
requirements.
Snow chains Should snow chains be necessary, they
must be mounted on the drive wheels
only.

Check with local authorities for possible
restrictions.
Use only Porsche-approved snow chains with
fine pitch links, so that enough
space remains between the chains and the inside of the wheel arches.
Drive wheels must rotate freely with chains
mounted to prevent damage to body, axle or
brake components. Follow instructions issued
by the supplier of the chains. Remove chains
as soon as roads are free of ice and snow.
New Tire Identifications
The European tire manufacturers have
changed their tire identification system for SR
and HR-tires pertaining to maximum
permissible speed and maximum load carrying capacity for belted tires. The following is an
example only.
During the transition period some tires might
show both old and new identification codes,
such as: 215/60 SR 15 M+S 80 Q. In this
instance, the new codes apply.
The identification codes for VR tires
remain unchanged; for example: 205/55 VR
16. (V = maximum permissible speed for radial tires, i.e. over 130 mph or 210 km/h).


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