Porsche 928 - WORKSHOP MANUAL 1977 Workshop Manual page 116

928
Wheels, Tires. Allanment
44
Cast fight-alloy disk wheels must not be fitted to the vehicles with four-piston fixed ca/ipers (as from
Model 86).
Club Sport version wheels (larger cutouts) have a different rim offset (see Page 44-01).
New tires should always be fitted to the front axle wherever possible (V the same wheels are fiied to
rear and front axles), as
1. the rear axle is more critical with regard to stability, and
2. in wet conditions, the front wheel must first steer a course which the rear wheel can follow to a
great extent. When replacing a defective tire, the difference in tread depths on one axle must not
be more than 30 %.
If a wheel is removed from the vehicle during service operations, the wheel stud next to the valve or,
in the case of 17.inch wheels (Cup Design), the wheel stud opposite the valve should first be
marked with red paint. (This is to ensure that the wheel is refitted in the same position relative to the
wheel hub or brake disc).
In addition, rotate the valve so It Is In the upper posftion or, in the case of 174nch wheels, In
the lower posltlon, before the wheel is tightened on the wheel hub (also refer to page 44 - 13).
This prevents the optimum balancing effect that was obtained by stationary balancing or by addi-
tional finish balancing from being lost. The lockable wheel must be fitted to the color-coded stud.
Refer to Technical Information Group 4 for further general information on tires (tire damage, tire
wear, storage, tire age)
Tire age:
High-speed tires VR'ZR in particular, must not be too old, under no circumstances older than
6 years. The age of a tire can be determined from the manufacturer's code which follows the DOT
code on the tire wall. The date of manufacture ist at the end of the code number. The identification
is followed by the manufacturing date. From 1990 to 1999, the three-digit mark is complemented by
a "triangle suffix" (differentiation mark).
Example:
DOTDMCP05Ym
2.2 = Production week 27
6 = Production year 1986
General assembly information, tires
Printed in Germany - XXXI, 1993
44-9