General Tire Mounting Instructions
General
Always use new rubber valves when changing tires!
Important: When mounting tires, observe the direction of rotation or inside/outside identification.
When mounting tubeless tires, check the sealing surface of the tire and the disk 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 (rabbit starts, hard cornering, etc.).
When mounting the tire beads, use only the tire mounting pastes specified below. The following can occur if an unsuitable mounting paste is used:
Turning of the tire on the wheel, fracture of the bead core when the tire is mounted and damage to the wheel surface by aggressive substances.
Important: Use only TIP TOP Universal, order No. 593 0601 (3.5-kg bucket) or Contifix as the mounting paste.
If Contifix is used, apply sparingly to the tire bead (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.
In order to prevent the tire from turning on the wheel when the vehicle is driven, also inform your customers that they should avoid extreme driving maneuvers (acceleration, braking) during the first 100 to 200 km with new or recently mounted tires. Mark the relative positions of the tire and wheel for reference if necessary.
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.
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). Matching (uncontrolled and controlled) is explained below.
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.
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 3 bar gauge pressure in order to ensure that they are seated properly on the wheel.
At the latest when the pressure reaches 3.0 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 an the other axle can cause a noticeable change in the familiar handing.
This is especially the case if new tires are mounted on the rear axle. This effect decreases with increasing tire mileage.
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.
The overview of summer and winter tires and wheels is included in Technical Information (TI).
Always observe the tire specification code when replacing summer tires. 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.
Tire age
High-speed ZR tires in particular should not be too old - never older than 6 years.
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.
For the years 1990 to 1999, the 3-digit code is sometimes supplemented by a "triangle suffix". (Distinguishing feature.)
Balancing weights
Type of balancing weights: Adhesive weights as used previously (no special version necessary).
Arrangement: Affix both weights on the inner side (arrows).*
*Observe program selection and operating instructions of the balancing machine.
Mounting wheel on vehicle
The wheels are mounted using M 14 x 1.5 wheel bolts. The wheel bolt consists of two parts that are permanently connected to each other. Other wheel bolts must not be used.
Use suitable commercially available tools (wrench size 19 mm). Never use an impact bolter to tighten the wheel bolts.
Always apply a thin coat of Optimoly TA (aluminum paste) (arrows) on the thread of the wheel bolts, on the shank and between the bolt head bearing surface and spherical cap ring (under the head).
Do not coat the spherical cap surface of the wheel bolts that faces the wheel (X).
In the case of heavy soiling, first clean the wheel bolt and the spherical caps in the wheel with a lint-free cloth.
Damaged wheel bolts must always be replaced. This damage includes mechanical damage to the thread, the spherical cap and damage resulting from seizure of the bolt head bearing surface and spherical cap ring.
It must be possible to rotate the spherical cap ring and shift it in axial direction on the bolt shank.
Rework on wheel bolts is impermissible.
Screw in wheel bolts by hand and then tighten evenly. Start at the top when tightening.
Always observe the specified tightening torque of 130 Nm (96 ft. lbs.).