WM, 4440IN Information On Tyres/Mounting Tyres: Information: Tyres
Tyre damage - caused while driving
If a tyre is damaged and it cannot be determined with absolute certainty that there is no ply damage - with all of its consequences - or if the tyre was thermally or mechanically overloaded due to a loss of pressure or other prior damage, we recommend replacement of the tyre in question for safety reasons.
Tyre damage - caused while removing/mounting tyres
When mounting tubeless tyres, check the sealing face of the tyre 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 tyres. When mounting the tyre beads, use only the specified tyre mounting pastes. The following can occur if an unsuitable mounting paste is used:
- Twisting of the tyre on the rim.
- Fracture of the bead bundle during mounting and if the seating pressure is too high.
- Damage to the tyre bead.
- Damage to the rim surface by aggressive substances.
Replacing tyres
Tyres should not be more than 6 years old!
Repairs to the tyres are not permitted nor is the use of inner tubes in tubeless tyres.
When replacing a tyre on an axle, make sure that the tread depth of the new tyre does not differ from that of the other tyre by more than 30%.
If new tyres are mounted or the tyres of one axle are replaced, tyres of the same make and with the same specification code must always be used on each of the two axles.
If tyres are replaced on one axle only, the different tread depth in relation to the other axle can cause a noticeable change in the handling the driver has become accustomed to. This is especially true if new tyres are mounted on the rear axle. This effect decreases with increasing tyre mileage.
The overview of summer and winter tyres is included in Technical Information (TI), information 4. When replacing summer tyres, pay close attention to the tyre specification number for the same make of tyre. The specification code (for example N0) distinguishes the summer tyres specially authorised by Porsche from other models of the same tyre type and size.
Customers should be informed that the full performance of new or newly mounted tyres is achieved only after driving the vehicle for a distance of 100 to 200 km (60 to 120 miles). Extreme driving manoeuvres (acceleration, braking) should be avoided.
Tyre storage
Tyres 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 tyre pressure by 0.4 bar (6 psi).
If the tyres are not mounted on wheels, store them in the vertical position. Tyres stored in vertical position should be turned every two weeks in order to prevent excessive flat spots. If the tyres are stacked in horizontal position, they will become severely deformed and cannot be seated in the rim flange easily when mounted.
Tyres 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 tyres that are in continual use. Hairline ageing cracks can occur on older tyres. If tyres are in use, the kneading action activates the plasticizer in the rubber and thereby prevents hardening and cracking.
Tyre identification (speed classes/tyre age)
Tyres should not be more than 6 years old!
The age of the tyre can be determined from the manufacturer's code, which is shown behind the DOT code on the tyre sidewall! The date of manufacture (the last four digits) is shown at the end of the code!
Example
| DOT DM CP 05 Y 2200 | 22 = production week |
| 00 = production year 2000 |