Table of Contents
Advertisement
CLUTCH A N D TRANSMISSIONS 7-20
COMPONENT PARTS REPLACEMENT
3.
4.
5.
6.
TRANSMISSION REPLACEMENT (EXC. CORVETTE)
Removal From Vehicle
1. Remove shift lever trim plate and dust boot.
Remove shift lever assembly.
Raise vehicle to desired working height.
Disconnect the speedometer cable from speedometer
driven gear fitting.
. ~ . •
Remove propeller shaft, then support engine at the
oil pan rail with a jack or other suitable support
capable of supporting the engine when transmission
is removed.
Disconnect shift lever bracket assembly from exten-
sion and remove all 3 transmission shifter levers
from shifter shafts, (leave linkage connected to
levers) and remove bracket assembly levers and
linkage.
Remove extension mount7 to-crossmember attaching
bolts.
Loosen transmission crossmember and move rear-
ward or remove.
Remove the transmission-to-clutch housing retaining
bolts and install two guide pins, J-1126, in top holes.
Slide the transmission straight back until the input
shaft is free of splines in the clutch disc.
Slide the transmission rearward to allow sufficient
clearance of input shaft and clutch housing. Then tilt
input shaft end of transmission downward and with-
8.
9.
10.
11.
draw transmission from vehicle.
installation to Vehicle
1. Raise transmission and rotate as necessary-to start
input shaft into clutch disc and slide transmission
forward until it bottoms against clutch housing. Re-
move guide pins.
2. Install the transmission-to-clutch housing retaining
bolts. Torque all four retaining bolts to 50 ft. lbs.
3. Raise engine and position extension mount to cross-
member, and loosely install the retaining bolts.
Tighten crossmember to frame retaining bolts.
4. Remove temporary support from engine, and torque
the extension mount retaining bolts.
5. Install propeller shaft.
6. Install control lever bracket assembly to transmis-
sion extension and connect shifter levers to shifter
shafts.
7. Fill transmission to level of filler plug hole with
correct lubricant specified in Section 0.
8. Lower vehicle and install shift lever assembly, check
shift pattern and adjust linkage as required.
9. Install trim plate and dust boot.
CORVETTE TRANSMISSION REPLACEMENT
Refer to similar procedure under 3-Speed Corvette
Transmission.
FOUR-SPEED (SAGINAW) TRANSMISSION
INDEX
Page
General Description
7-20
Maintenance and Adjustments . .
7-21
Shift Linkage Adjustment. .
7-21
Speedometer Driven Gear and
Oil Seal . . . . . . . . . . . . . . . .
(See Muncie 4-Speed)
Side Cover
7-22
Page
Removal
. . ,
7-22
Disassembly
. .
7-22
Assembly . . .
7-22
Installation
.
7-22
Extension Oil Seal
(See Muncie 4-Speed)
Transmission Replacement
(See Muncie 4-Speed)
GENERAL DESCRIPTION
The Saginaw four speed fully synchronized (all forward
gears) transmission incorporates helical drive gears
throughout.
The main drive gear is supported by a ball bearing at
the front end of the transmission case and is piloted at its
front end in an oil impregnated bushing mounted in the
engine crankshaft. The front end of the mainshaft is
piloted in a row of roller bearings set into the hollow end
of the main drive gear and the rear end is carried by a
ball bearing mounted in the front of the extension housing.
The countergear is carried on a single row of rollers
at both ends while thrust is taken on thrust washers lo-
cated between the ends of the gear and the thrust bosses
in the case. Ah anti-rattle plate assembly at the front of
the countergear provides a constant spring tension be-
tween the counter and clutch gears to reduce torsional
vibrations. The sliding reverse idler gear is carried on
a bushing finish bored in place. It rotates on a short
idler shaft retained by a woodruff key.
The synchronizer assemblies consist of a clutch hub,
clutch sleeve, two clutch key springs and three energizer
clutch keys and are retained as an assembly on the main
shaft by a snap ring.
A great deal of similarity and interchangeability now
exists between the new 3 and 4-speed Saginaw trans-
missions.
However, the synchronizer assembly at the front of the
mainshaft is used for the third and fourth rather than the
second and third shift. The synchronizer assembly at
the rear of the mainshaft is used for the first and second
rather than the first and reverse shift. Gear teeth cut
in the first and second synchronizer sleeve (reverse gear)
distinguish it from the third and fourth synchronizer
sleeve.
Starting from the front, gears on the mainshaft are
third, second and first rather than second, first and re-
verse. A fourth blocker ring is used between the 1-2
synchronizer assembly and first gear on the four-speed
transmissions.
The cover on the new four-speed transmission is lo-*
cated on the left-hand side of the case. It is similar to
the three-speed cover with the addition of a reverse
shifter shaft assembly, detent ball and detent spring.
Disassembly and assembly procedures are covered in
this section.
CHEVROLET CHASSIS SERVICE MANUAL
Advertisement
Table of Contents
