Pontiac FIREBIRD 1972 Service Manual page 854

THREE SPEED MUNCIE TRANSMISSION
7B- 15
NOTE: Synchronizer hubs and sleeves are a se-
lected assembly and should be kept together as
originally assembled but the keys and two
springs may be replaced if worn or broken.
a. Mark hub and sleeve so they can be matched
upon reassembly.
b. Push hub from sliding sleeve; keys and springs
may be easily removed.
c. Reassemble by placing three (3) keys and two (2)
springs into position (one spring on each side of
hub), so that all three keys are engaged by both
springs.
d. Slide sleeve onto hub, aligning marks made before
disassembly.
MAINSHAFT (Fig. 76-1 1)
ASSEMBLE
1. With rear of mainshaft upward, install 1st speed gear
with its clutching teeth upward. Face of gear will butt
against shoulder of mainshaft.
2. Install blocker ring (all three blocker rings are identi-
cal) with its clutching teeth downward over synchro-
nizing surface of 1st speed gear.
3. Install 1st & Rev. synchronizer assembly with fork
slot up (Fig. 7B- 13) and, making sure that notches of
blocker ring align with keys of synchronizer assem-
bly, press assembly onto splines of mainshaft until it
bottoms out.
4. Install synchronizer hub-to-mainshaft snap ring,
making sure that snap ri.ng is seated fully in its main-
shaft groove. Both synchronizer hub snap rings are
identical.
5. Install reverse gear with its clutching teeth down-
ward and install its bronze thrust washer, aligning its
flats onto the mainshaft.
SLEEVE SLEEVE
HUB HUB
4
FRONT
-
Fig. 78-13 Synchronizer Sleeve and Hub Assembly
6. Install rear bearing with its snap ring slot downward
and press it onto the mainshaft.
7. Install rear bearing snap ring into its mainshaft
groove.
8. Install speedometer drive gear and retaining clip on
mainshaft.
9. With front of mainshaft upward, install 2nd speed
gear with its clutching teeth upward. Rear face of
gear will butt against shoulder of mainshaft.
10. Install blocker ring with its clutching teeth down-
ward over synchronizing surface of 2nd speed gear.
11. Install 2nd & 3rd synchronizer assembly with fork
slot downward (Fig. 7B-13) and, making sure that
notches of blocker ring align with keys in synchro-
nizer assembly, press it onto splines of mainshaft un-
til it bottoms out.
12. Install synchronizer hub-to-mainshaft snap ring.
13. If side cover was disassembled, reassemble as ou-
tlined under MINOR REPAIRS.
TRANSMISSION
ASSEMBLE
NOTE: For ease in assembling and installng
coun tergear, a tool may be fabricated using a I
"
diameter dowel stock, cut to length of 9 5/8".
Load a row of bearing rollers (29), a bearing washer,
a second row of bearing rollers (29) and a second
bearing washer at each end of the countergear. Use
fabricated tool or heavy grease to hold them in place.
Place countergear assembly, along with a tanged
thrust washer (tang away from gear) at each end,
through rear opening of case and install countershaft
and woodruff key from rear of case. Make sure that
thrust washer tangs are aligned with their notches in
case and that end flat of countershaft is flush with
rear face of case.
Lay reverse idler gear in case. Do not install reverse
idler shaft yet.
Using snap ring pliers, expand snap ring in extension
housing and position extension housing over rear of
mainshaft and onto rear bearing. Seat snap ring into
groove of rear bearing.
With heavy grease holding them in place, load main-
shaft pilot bearings (16) into main drive gear cavity