Chevrolet 1980 Light Duty Truck Repair Manual page 386

7B-40 M A N U A L TR A N SM IS S IO N
F ig . 7 B - 7 L ~ S h if t e r S h a f t In s t a ll a t i o n
5. Install new gasket on retainer and install retainer on
transmission case (when assembling transmission).
M A IN S H A F T A S S E M B L Y
Disassembly (Fig. 7B-14L)
1. Remove first speed gear and thrust washer.
2. Remove snap ring in front of 3rd-4th synchronizer
assembly.
3. Remove reverse driven gear.
4. Press behind second speed gear to remove 3rd-4th
synchronizer assembly, 3rd speed gear and 2nd speed gear
along with 3rd speed gear bushing and thrust washer (Fig.
7B-15L).
5. Remove 2nd speed synchronizer ring.
6
. Supporting 2nd speed synchronizer hub at front face,
press mainshaft through removing
OIL SLINGER
O VE RH AU L M A N U A L
REVERSE
3 R D /4 T H
1 S T / 2 N D
1
st speed gear bushing
RETAINER RING
SNAP RING
Fig. 7 B -8 L -D rive Gear A ssem bly
2
and nd speed synchronizer hub.
7. Split 2nd speed gear bushing with chisel and remove
bushing from shaft. Exercise care not to damage mainshaft.
Inspection
1. Wash all parts in cleaning solvent.
2. Inspect mainshaft for scoring or excessive wear at
thrust surfaces or splines.
3. Inspect clutch hub and clutch sleeve for excessive
wear and make sure sleeve slides freely on clutch hub. Also
check fit of clutch hub on mainshaft splines.
Third and fourth speed slutch sleeve should slide freely
on third and fourth speed clutch hub but clutch hub should
be snug fit on shaft splines.
4. Inspect 3rd speed gear thrust surfaces for excessive
scoring and inspect third speed gear mainshaft bushing for
excessive wear. Third speed gear must be a running fit on
mainshaft bushing and mainshaft bushing should be press
fit on shaft.
5. Check second speed thrust washer for excessive
scoring.
6
. Inspect 2nd speed gear for excessive wear at thrust
surface. Check synchronizer springs for looseness or
breakage.
7. Inspect second gear synchronizing ring for excessive
wear.
8
. Inspect bronze synchronizer cone on 2nd speed gear
for excessive wear or damage. Also inspect clutch gear
synchronizer cone and third speed gear synchronizer cone
for excessive wear or damage.
First and reverse sliding gear must be sliding fit on
synchronizer hub and must not have excessive radial or
circumferential play. I f sliding gear is not free on hub,
inspect for burrs which may have rolled up on front end of
half-tooth internal splines and remove by honing as
necessary.