General Procedure For Suspension Alignment
Perform suspension alignment using an electronic wheel-alignment analyzer. Measurement procedures are described in the operating instructions for the wheel-alignment analyzer used.
For nominal value for front and rear axles, refer to the Technical data.
> 4495TW ADJUSTMENT VALUES FOR SUSPENSION ALIGNMENT
To rule out any possibility of erroneous measurements, the following preconditions must be met before alignment and particular attention should be paid to the following points:
Empty weight of vehicle according to DIN 70020, i.e. vehicle in ready-to-drive condition with full fuel tank and including tools but without driver or additional weights.
Joint and wheel-bearing play OK (wheel-bearing play cannot be adjusted).
Tire pressure in accordance with regulations, fairly uniform tire tread.
Use > 9229/1 - puller hook to pull off the hub caps (in order to fit the quick-clamping holders).
Quick-clamping holder with adapter (for the measured-value pickups/measuring reflectors) correctly secured to the wheels.
Use > VAS 6918 - Quick-Clamping Unit to secure the measured-value pickups/measuring reflectors to the wheels. Any previously used quick-clamping holders that are available can also be used.
The self-centring quick-clamping holders are positioned centrally (with the claws first) in the center of the rim and are tightened in the rim by turning the straining ring (clockwise).
Self-centring quick-clamping holder (VAS 6918)
Receiving surfaces for the quick-clamping holders on the wheels and the adapter surfaces must be clean and flat. Always check the flat surface on the wheels precisely in particular before fitting the quick-clamping holders.
Strictly comply with maintenance intervals for measuring equipment and measuring platform. If the levelling of the measuring platform or measuring station is done in-house, levelling equipment is required. A spirit level is not sufficient.
Skilled handling of measuring equipment and measuring platform.
Sliding plates with transverse motion (rotary motion) at the rear axle are advisable.
Refer to the Technical Literature provided by Porsche AG, the manufacturer of the measuring equipment and the manufacturer of the measuring platform.
Do not treat measured values as a whole, but very critically with regard to driving dynamics, high-speed strength of the tires, tire wear and cost/benefit effects (time required for correction of insubstantial deviations). The toe values are of decisive significance for driving dynamics and tire wear.
If the vehicle is measured front and rear, check and adjust the wheel alignment values at the rear axle first. The camber values at the front axle are valid if the wheels are in the straight-ahead position. Steering wheel and steering gear in center position when toe is being adjusted.
Before wheel alignment values are adjusted at front and rear axles, it is recommended that the vehicle height be checked at the DIN empty weight. Conclusions can then be drawn about wheel alignment values in the event of any suspension alignment that becomes necessary later.