Tires/Wheels - Winter Tires/Snow Chains/Wheels
Boxster1/04 4440
Binder - Group 4, Running Gear Replaces bulletin Group 4, # 1/03 dated 102-03.
Date: 3-26-04
Winter Tire, Wheel, & Snow Chain Applications
Vehicle Type:
Boxster / Boxster S
Model Year:
As of 1997 (V)
Concerns:
Winter tires, wheels, snow chains and spacer rings - status 12/2003
Makes/Types:
Approved Winter Tire Makes and Types
Mounting Instructions:
Instructions for proper tire mounting are located on the tire.
If there are no mounting instructions on the tire sidewall, the tire must be mounted so that the DOT code is visible from the outside.
Tire Pressure:
This tire pressure applies only to ne tire makes and types approved by Porsche, and is specified for cold tires (approx 20° C/68° F). The tire pressures must never be lower than the specified values.
Tire Sizes:
Approved Winter Tire, Wheel and Spacer Ring Sizes
Wheels:
Overview of Porsche wheels for winter tires.
Caution!
Risk of surface damage if the tires/valves are not mounted according to regulations and/or if the wheel surface is not cleaned/cared for correctly.
> Carry cut tire removal and mounting with a bead holding-down device only
> Use a leather pad on the rim fiance to support the valve insertion tool.
> Use only the Porsche centering clamping set for balancing.
> Do not clean the wheels with brushes (speak to car wash operator).
> Deep scratches in the surface coating of the wheel cannot be repaired by polishing.
Fastening Spacer Ring/Wheel:
The 5 mm thick spacer rings are mounted on the wheel hubs together with the brake discs using longer countersunk screws (M6x16), P/N: 900 269 106 09.
Tightening torque: 10 Nm (7.5 ftlb.)
The 5 mm spacer ring must remain on the vehicle when mounting the spare wheel.
Wheel mounting must be done using the 5 mm longer wheel bolts of the 911 GT3 P/N: 996 361 203 90. These GT3 wheel bolts are marked with GT or with a red color on the face surface (arrow) of the bolt head, or the rotating spherical cap is galvanized in red.
Dimension X approx. 50 mm.
Tightening torque: 130 Nm (96 ftlb.)
Important!
If the 5 mm thick spacer rings are removed from the vehicle again, the standard wheel bolts and countersunk screws (M6x12) must be used again. The scope of parts required for this is listed in the following table:
The 17 mm spacer rings are mounted on the wheel hubs using the standard wheel bolts, Part No. 996 361 203 00/01 (dimension X = approx. 45 mm).
Tightening torque: 130 Nm (96 ftlb.).
The wheels are mounted on the 17 mm spacer rings using wheel nuts. Part Nos. 999 182 003 36.
Tightening torque: 130 Nm (96 ftlb.).
Note:
The 17 mm spacer ring must be removed when installing the spare wheel.
The 17 mm spacer ring must be removed when mounting the spare wheel.
Checking Tire Clearance:
There must be a gap of at least 5 mm between the outer side of the tire and the wing seam when compressed. If the gap is smaller than 5 mm, then change the rear axle camber towards positive. The adjustment value must lie between the following values:
Standard running gear -1°20' and -0°50'
Sport-type running gear -1°30' and -1°
All other adjustment values for suspension alignment remain unchanged except for the vehicle height tolerance of the rear axle.
Rear Axle Adjustment:
Snow Chains:
Porsche offers the following snow chains as accessories.
Observe mounting instructions from the chain manufacturer!
For safety reasons, vehicles with snow chains must not be driven faster than 30 mph (50 km/h). Observe the respective road traffic regulations.
Navigation Systems:
After a wheel change, the full locating accuracy is attained only after a trip of approx. 30 cues (50 km)
(if possible on the highway and at a speed > 38 mph (60 km/h). Additionally, high slip of the wheels
(e.g. wheel spin on snow) can result in temporary incorrect positioning.
General:
Always use new valves when changing tires:
Rubber valves. not for 18-inch Turbo I wheels, Part Number - 900 265 001 50 and 000 044 600 00
Steel valves, only for 18-inch Turbo I wheels, Part Number - 993 361 073 00
Always observe any possible instructions concerning the rolling direction and/or specifying which side the tires must be mounted on.
Coat the tire beads and humps with mounting lubricant before mounting the tire. This ensures that the tire beads will slide over the humps easily. In order to prevent the tire from turning on the wheel. avoid extreme driving maneuvers (acceleration and braking) during the first (100 to 200 miles) with new or recently mounted tires.
In order to optimise smoothness of rolling, it is appropriate - and necessary in individual cases - to mount the tire in a certain (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 120° if necessary in order to achieve an acceptable value with regard to rolling smoothness (true running, imbalance and weight 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 weight distribution of the balance weights) than can be achieved with uncontrolled matching. Maximum permissible radial runout and lateral runout of the wheels < 0.7 mm. Maximum permissible radial runout and lateral runout of the wheels with tires 1.25 mm. Values < 1.50 mm - ideally approx 0.5 mm - are desirable.
The mounting pressure (seating pressure) of 58 psi/4.0 bar overpressure must not be exceeded before both tire beads are evenly seated on the rim flange.
If new tires are to be mounted or the tires of one axle are to be replaced, tires of the same make, the same type 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 from that 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.
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 %.
If a tire is damaged and it cannot be determined with absolute certainty that there is no ply camage - 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.
Repairs on "ZR" tires are not allowed, as is the use of inner tubes in tubeless tires. Tires age due to chemical and physical processes. which can impair their function. Tires that are stored unused for an extended period harden and become brittle faster than tires that are in continual use.
Hairline aging cracks can occur on older tires. On tires in continual use, the kneading action activates the plasticizer in the rubber and thereby prevents hardening and cracking.
Therefore, attention should be paid not only to the tread depth but also to the age of the tire. Tires should not be older than 6 years. The age of the tire can be determined via the DOT code on the sidewall, which indicates the production date of the tire: e.g. DOT 2201=22nd week of 2001.
Tires/complete wheels 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. Optimum conditions for proper storage of the complete wheels are provided by the Original Porsche storage stand (trolley), Part Number 000 044 000 38.
If the tires are not mounted on wheels, it is best to 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 in the rim flange easily when they are mounted.
Working Times:
Literature:
Boxster Technical Manual, Group 4
Repair: 44 - Wheels and tires, adjustment values for suspension alignment, Pages 44-1- on
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