Porsche 1972 911 Workshop Manual page 520

REAR AXLE CHANGES
1. Beginning with 1972 models, rear axle shockabsorbers have been modified. The outside diameter
and overall length of the shockabsorbers has been increased:
Outer diameter
new:
old:
Extended length
new:
old:
Closed length
new:
old:
2. The BOGE shockabsorbers are standard on the rear axle. BILSTEIN or KONI shockabsorbers are
optional.
The various shockabsorber types can be distinguished by their color:
BOGE
KONI
BILSTEIN
To allow for the larger shocks, the lower mount has been moved rearward 10 mm. The upper mounting
has also been moved slightly forward and in towards the vehicle longitudinal axis. This change was also
necessary due to the new transmission which has its axle flanges approximately 10 mm further to the
rear.
The shockabsorber mounting bolt has been changed from the former 12 mm diameter to 1 4 mm dia-
meter.
-
BEGINNING W I T H 1 9 7 2 MODELS
62 mm (2.44 in.)
58 mm (2;28 in.)
599 "2.0 mm (23.59
407.5 1 2 . 0 mm (16.04
390 2.5 mm (15.37
black
red
green
R e a r A x l e D e s c r i p t i o n
0.08 in.)
0.08 in.)
0.10 in.)
9 1 1