Tires (Summer) - Approved Manufacturers and Types
Boxster3/99 4440
Binder - 4, Running Gear
This bulletin replaces bulletin,
Group 4, # 2/99, Dated 6-8-99.
10-28-99
Summer Tire and Wheel Summary
Vehicle Type:
Boxster (986)
Model Year:
As of 1997 (V)
Concern:
Approved Summer Tire Manufacturers and Types
Information:
Important:
18 inch wheels are only approved for the 986 as of model year 1998 (W)!
"NO", "N1", "N2", "N3" and "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:
Arrow with inscription "Rotation" = directional
Inscription "inside\outside" = side-directional
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:
16, 17 and 18 Inch Wheels Emergency Spare Wheel
Front 2.0 bar 4.2 bar
Rear 2.5 bar 4.2 bar
The above tire pressures are valid only for tires approved by Porsche. The tire pressures must be checked and adjusted cold (approximatly. 20° degrees Celsius or 68° degrees Fahrenheit). Do not under inflate tires, the values listed cannot be lower under any circumstance.
Tire Sizes:
Approved Summer Tires and Wheels
Wheels:
Overview of Porsche wheels for use with summer tires. The wheel description (wheel size, offset, part number and Porsche trademark ) is indicated on the inside/outside of the wheel.
Wheel Fastening:
Securing of the wheels to the hub occurs with five lug bolts M14 x 1.5 (19 mm socket size). Tightening torque = l3O Nm (95 ft/lb).
General Comments:
The rubber valve stem (not for 18" Turbo wheels) part numbers1 900 265 001 50 or 000 044 600 00 including cap should be replaced with the mounting of each new tire.
For 18" Turbo wheels use part number, 993 362 073 00, steel valve.
Observe tire mounting instructions from page one and two regarding direction of rotation and or side direction when mounting. Use lubricant 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 if this should occur.
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 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 on ZR tires and use of tire tubes are not allowed.
Other Tire Handling Notes:
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 (includes spare tire).
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 about 0.4 bar.
Tires that are not mounted should be stored in a vertical position. We recommend rotating the tires every two (2) weeks to avoid flat spotting. If tires are stored in a horizontal manner they may deform and be difficult to install.
The original Porsche tire storage system, part number, 000 044 000 22 is available from the parts department to store complete wheel/tire sets.