Pontiac FIREBIRD 1972 Service Manual page 347

NON TYPE C DIFFERENTIAL 4A-23
Fig. 4A-33 Pinion Gauge Tools Installed
-
A and G Series
Fig. 4A-35 Checking Pinion Depth
7. Install bearing caps over gauge shaft discs.
ing the indicator pad. Set the dial indicator on zero,
then depress the dial indicator until the needle rotates
3/4 turn clockwise. Tighten the dial indicator in this
8. Position gauge shaft so that the dial indicator rod
contacts the gauging area of 5-21777-26 for B Series
position.
vehicles, or the "A" gauging area of 5-2 1777-2 for A
6. Install discs on gauge shaft assembly as shown in Fig.
and G Series. Rock gauge shaft slowly back and forth
4A-33 and 4A-34 and position in the carrier so that
until the dial indicator records the greatest deflection,
(the point where dial indicator needle changes rota-
the dial indicator contact rod is directly over the
tional direction) at the point of largest deflection, set
gauging area of the gauge plate. The discs must be
dial indicator to zero (Fig. 4A-35). Repeat rocking
fully seated in the side bearing bores.
action of gauge shaft to verify the zero setting.
Fig. 4A-34 Pinion Gauge Tools Installed
-
B Series
9. After the zero setting is obtained, rotate gauge shaft
until the dial indicator rod is removed from the gaug-
ing area. The dial indicator will read the pinion depth
directly.
10. Select correct pinion shim to be used during pinion
reassembly on the following basis B Series
-
Fifteen
(15) shims are available in increments of (.002") two
thousandths from .02OV to .05OW.
A or G Series
-
Ten (10) shims are available in increments
of (.002") two thousandths from .020n to .038".
a. If reusing production pinion, and pinion is
marked
"+"
(plus), correct shim will have a
thickness equal to gauge reading plus the amount
specified on pinion.
b. If production pinion is marked "-" (minus), cor-
'
rect shim will have a thickness equal to gauge
reading, less the amount specified on pinion.
c. If using production or service pinion which has
no marking, the correct shim will have a thick-
ness equal to the gauge reading.