Wheels/Tires - Summer Applications
911(996)8/00 4440
Binder - Group 4, Running Gear
This bulletin replaces bulletin,
Group 4, # 5/99, dated 10-29-99.
11-10-00
Summer Tire and Wheel Summary
Vehicle Type:
911 Carrera (996)
Model Year:
As of 1999 (X)
Concern:
Approved Summer Tire Manufacturers and Types
Information:
Approved summer tire makes and types
"N0", "N1", "N2", "N3" or "N4" indicates a specification identification of the tires. The complete "N" number must be present and visible on the outside of the tire side wall near the type-designation. Only use tires of the same manufacturer, tire type and "N-" specification on one vehicle.
Observe tire markings on side wall for correct mounting, and rotational direction.
When markings are omitted on the side wall, mount the tire in such a manner that the DOT inscription is visible from the curb side.
Inflation Pressures:
The above tire pressures are valid only for tires approved by Porsche. Tire pressures must be checked and adjusted cold (approximately 200 degrees Celsius or 680 degrees Fahrenheit). Tire pressures can never be lower than what is specified above.
Do not drive on under-inflated tires under any circumstance!
Tire Sizes:
Wheels:
Wheel Fastening:
Secure the wheels to the hubs with five (5) Porsche lug bolts, M14 x 1.5 (19 mm socket size), tightening torque 130 Nm (96 ft lb.).
Notes:
The rubber valve stem (not for 18" Turbo wheels) should always be replaced with the mounting of each new tire part number, 900 265 001 50 or 000 044 600 00, including cap.
For 18" Turbo wheels use part number, 993 361 073 00, steel valve.
Use approved assembly paste to facilitate mounting and to prevent damage to tire beads. Avoid extreme acceleration and braking for the first 60 to 120 miles to prevent tire movement on the wheel. Wheel balancing accuracy may be affected should this occur.
Maximum allowable tire movement on the wheel rim is 20 mm.
Optimal wheel balancing and minimal tire noise can be achieved by matching the tire run-out to the wheel. Please refer to the following comments on controlled and uncontrolled matching.
Uncontrolled matching:
If required, move tire on wheel by 90 or 120 degrees to find acceptable values regarding out of round conditions, imbalance, and wheel balancing weight application.
Controlled matching:
Use balancing equipment with matching program capability. Values can be optimized.
Maximum permissible axial and lateral run out of wheels <=0.7 mm.
Maximum permissible axial and lateral run out of tire and wheel assembly <=1.25 mm (desired value <=1.0 mm).
When mounting tires do not exceed inflation pressure of 4.0 bar (58 psi) while seating tire beads.
When new tires are mounted on one axle always use a matched set from the same tire manufacturer with the same "N" designation. The handling characteristics of the vehicle may be affected by differing tread depths between front and rear axle tire sets. This effect is especially true when the rear tire set has been replaced. Use caution during break in of tires.
When handling tire complaints and tire damage is determined, the tire should be replaced. The tire should also be replaced if you are uncertain about cord damage or if the appearance of overheating makes the tire suspect in any manner.
When replacing a single tire on one axle, the difference in tread depth on the axle may not exceed 30%. Repairs to ZR tires, or the use of tire tubes are not permitted.
The chemical and physical properties of a tire may be affected by long storage time, and the rubber compound may harden over time. Tires which are in constant use or motion will maintain a pliable compound and delay the hardening process. Therefore, the concern should not only be tread depth but the age of the tire as well. Tires should not be older than six years from date of manufacture. The tire age can be determined from the DOT stamp on the outside of the tire sidewall. For example, "DOT...067" = week 6, 1997.
Generally, tires should be stored in a cool, dry, and well ventilated area. Keep away from sunlight. Avoid contact with fuels, grease, oils, and other chemicals.
Mounted wheel sets may be stacked if required. It is recommended to increase tire pressure by approx. 0.4 bar (6 psi) during storage.
Tires that are not mounted should be stored in a vertical position. Turn tires every two (2) weeks to avoid flat spotting. If tires are stored in a horizontal manner, they may deform and become difficult to install.
For proper storage of the complete wheel, Porsche has available through it's Parts Department a storage cart, part number, 000 044 000 38.
Spacer Ring/Wheel Mounting:
The 5 mm spacer rings are mounted on the wheel hubs using longer countersunk screws (figure 1), part number, 900 269 106 09. Tightening torque: 10 Nm (7.5 ft lb).
When using the wheel spacer, part number, 996 361 605 90, 5 mm longer wheel bolts (figure 2), part number, 996 361 203 90 must be used. These wheel bolts are marked with "GT" or with a red color on the head surface (arrow in figure 2), or the rotating spherical cap is red.
Dimension Z = Approx. 50 mm
Tightening Torque: 130 Nm (96 ft lb)
Note:
The 5 mm spacer ring must remain installed whenever the spare tire mounted.
Navigation System:
After a tire and wheel change, the full locating accuracy is attained only after a trip of approximately 30 miles.