General Tire Mounting Instructions
General tire mounting instructions
Mounting instructions
General
Information
^ Always use new valves when changing tires! Rubber valves are primarily used. Steel valves (part No. 993.361.073. 00) are used for Turbo wheels (not for Turbo Look wheels).
^ The initially represented procedure, steel valves do not generally need to be changed, is invalid. Previous written publications should be altered accordingly.
^ When fitting tires, the direction of rotation and the inner and outer sides should be noted.
^ Use only TIP TOP Universal, order No. 593 0601 (3.5 kg bucket) or Contifix as the mounting paste.
When mounting tubeless tires, check the sealing surface of the tire and the disc wheel for cleanliness and any signs of damage. Bear in mind here that the bead base performs the sealing function on tubeless tires. If the bead edge has to perform the sealing function, air can escape when the vehicle is driven aggressively.
When mounting the tire beads, use only the prescribed tire mounting pastes. The following can occur if an unsuitable mounting paste is used:
^ twisting of the tire on the rim
^ fracture of the bead core during mounting
^ damage to the rim surface by aggressive substances
If Contifix is used, apply sparingly to the tire beads (due to risk of the tire turning on the wheel). If possible, the vehicle should not be driven for 24 hours after tire mounting or matching.
Information
^ Customers should be informed that the full performance of new or newly mounted tires is achieved only after a distance of 100 to 200 km (60 to 120 miles) has been driven. Extreme driving maneuvers (acceleration, braking) should be avoided.
^ The absolute limit on how far the tire can turn on the wheel must be regarded as 20 mm. An optimum balancing result will be worsened in this case.
^ Mark the relative positions of the tire and wheel for reference.
In order to optimize smoothness of rolling, it is expedient - and necessary in individual cases - to mount the tire in a favorable position with respect to the wheel (matching).
Uncontrolled matching
Turning the tire on the wheel by 90° or 180° if necessary in order to achieve an acceptable value with regard to rolling smoothness (true running, imbalance and distribution of balance weights).
Controlled matching
With a balancing machine with matching program. In most cases, this produces an even better result with regard to the rolling smoothness (true running, imbalance and distribution of the balance weights) than can be achieved with uncontrolled matching.
Installation
Maximum permissible radial runout and lateral runout of the light alloy wheels = 0.7 mm. Maximum permissible radial runout and lateral runout of the wheel with tire = 1.25 mm. Values less than 1.0 mm - better around 0.5 mm - are desirable.
^ After mounting the tubeless tires, inflate them without valve insert to approximately 4.0 bar gauge pressure in order to ensure that they are seated properly on the wheel. At the latest when the pressure reaches 4.0 bar, the tire beads must pop out of the deep bed and over the hump of the wheel shoulder in order to avoid fractures of the bead core. If necessary, interrupt the process and coat all necessary surfaces with lubricant (tire mounting paste) again. Then repeat the process. Screw in the valve insert and set the prescribed tire pressure.
If new tires are to be mounted or the tires of one axle are to be replaced, tires of the same make and with the same specification code must always be used on each of the two axles. If tires are replaced on one axle only, the different tread depth than on the other axle can cause a noticeable change in the familiar handling. This is especially the case if new tires are mounted on the rear axle. This effect decreases with increasing tire mileage.
Information
^ If a tire is damaged and it cannot be determined with absolute certainty that there is no ply damage - with all of its consequences - or if the tire was thermally or mechanically overloaded due to a loss of pressure or other prior damage, we recommend replacement of the tire in question for safety reasons.
^ When replacing a tire on an axle, make sure that the tread depth of the new tire does not differ from that of the other tire by more than 30 %.
^ Repairs on ZR tires are impermissible, as is the use of inner tubes in tubeless tires.
^ When replacing summer tires, pay close attention to the tire specification number.
The specification code N1, N2, N3 or NO distinguishes summer tires expressly approved by Porsche from other versions of the same tire type and size.
Balancing weights
Type of balancing weights: Adhesive weights as used previously (no special version necessary). Also refer to the spare parts catalogue.
Affix both weights on the inner side (arrows).
Information
^ Observe program selection and operating instructions of the balancing machine.
Navigation system
After a wheel change, the full locating accuracy is attained only after a journey of approx. 50 kilometers (if possible on the motorway and at a speed > 60 km/h). Furthermore, high wheel slip (e.g.: wheel spin) can result in temporary incorrect positioning.
Wheel storage
Tires must be stored in a cool, dry and dark room with adequate ventilation. They must never come into contact with fuel, oil, grease or chemicals. Complete wheels can be stacked for storage. It is advisable to increase the tire pressure by 0.4 bar.
If the tires are not mounted on wheels, store them in vertical position. Tires stored in vertical position should be turned every two weeks in order to prevent excessive flattening. If the tires are stacked in horizontal position, they will become severely deformed and cannot be seated on the rim flange easily when they are mounted.
Optimum conditions for proper storage of the complete wheels are provided by the Original Porsche storage stand (trolley), part number: 000.044.000.38.
Tires age due to physical and chemical processes, which can impair their function. If they are stored for an extended period, they will harden and become brittle faster than do tires that are in continual use. Hairline ageing cracks can occur on older tires. If tires are in use, the kneading action activates the plasticizer in the rubber and thereby prevents hardening and cracking.
Tire age
Tires should not be older than 6 years. Not even the spare wheel.
Information
^ The age of the tire can be determined via the manufacturer's code, which is listed behind the DOT code on the tire sidewall. The date of manufacture (the last three digits) is located at the end of the code (up to 1999, the last 3 digits or as of 2000, the last 4 digits).
^ For the years 1990 to 1999, the 3-digit code is sometimes supplemented by a triangle suffix.
