Porsche 928 Workshop Manual page 850

39
Differential/Transaxle System
(128
ADJUSTING DRIVE PINION AND RING GEAR
Note
Carelul adjustment of the drive pinion and ring gear is important to guarantee a long service life and quiet
running for the final drive. This is why drive pinions and ring gears are matched during production and
checked on special testing machines for the most favorable surface appearance and low noise levels in
both directions of rotation. The position of quietest running is determined by moving the drive pinion in
an axial direction, keeping the ring gear within specified backlash tolerances. The deviation 't" from the
design dislance 'R' is measured and inscribed on the face of the drive pinion. Ring gears and drive pinions
are designed in such a manna that deviation "I" is always added to design distance 'Y; is always given
with 3 + sign.
R = Design distance (G 28. 03 =
12.70
mm/G 28.05 = 70.10 mm)
I = Deviation from R given in 1,100 mm
1 = Deviation I
2 z Pair code
3 = Backlash
39 - 12
Adjusting Drive Pinion and Ring Gear
Printed in Germany