Rocking-Yoke Type Transmission - Cadillac 1937 LaSalle VVI Information

TRANSMISSION
117
General Description
Synchro-mesh transmissions of two different
types are used on the 37-series cars. A n inertia
type transmission, as shown in Plate 49 is used
on Series 37-50, 60, 65, 70, 75 and 85 cars. In
this transmission, synchronizing drums are con-
trolled by detent springs mounted on the high
and intermediate speed coupling. A rocking
yoke type transmission, as shown in Plate 50, is
used on the 37-90, V-16.
The synchronizing mechanism in both types
consists p r i m a r i l y of two cone-type friction
clutches, one for second gear and one for high
gear. E a c h clutch is comprised of a sliding
bronze drum, a steel cone on the gear, and a slid-
ing gear coupling.
INERTIA T Y P E TRANSMISSION
T h e most important features of construction in
the inertia type transmission are as follows. T h e
use of helical gears in all speeds. The location of
the transmission cover at the bottom of the trans-
mission case. T h e location of the shifter shafts
at the side instead of the top of the transmission.
T h e use of three large ball bearings and a small
roller bearing at the front to support the m a i n
shaft. The use of needle roller bearings at the
countershaft supports. T h e use of a p i n type
synchronizing unit. A cross section view of this
transmission is shown in Plate 49.
T h e synchronizing drums in this transmission
are controlled by flat springs mounted in slots
in the sliding gear coupling, and the cam action of
the pins connecting the high and the intermediate
drums. W h e n shifting gears, the d r u m is moved
into contact w i t h the cone and held there during
the synchronizing period by the action of the
pins compressing the springs. F u r t h e r movement
of the gear shift lever brings the sliding coupling
into mesh internally with the transmission gear
and completes the shift.
R O C K I N G Y O K E T Y P E TRANSMISSION
T h e principal features of construction in the
rocking yoke type transmission are shown in
Plate 50. In this transmission helical gears are
used in all forward speeds. T h e main shaft and
transmission extension are supported by three
large ball bearings and a small roller bearing at
the front end of the shaft as a pilot bearing. T h e
constant-mesh gears on the m a i n shaft are sup-
ported by tapered roller bearings. The counter-
shaft is supported at each end by large ball
bearings.
T h e synchronizing drums in this transmission
are operated by yokes pivoted on eccentrics which
are fastened to adjusting quadrants on the outside
of the transmission case. M o v i n g these quadrants
up or down shortens or lengthens the yoke travel.
M o v e m e n t of the yokes is controlled by cams
machined on the shifter shaft. These cams engage
the rollers of the two oil-controlled plungers in
the yokes.
P R O P E L L E R S H A F T E X T E N S I O N
A propeller shaft extension housing is fitted to
the rear of the transmission on all 37-series cars.
T h i s extension housing permits the use of a
shorter propeller shaft, having less whip and
requiring less clearance under the body. It also
is used as the rear support for the power plant.
The- V - 1 6 is the only 37-series car using a
transmission extension shaft, as this extension is
integral w i t h the m a i n shaft on series 37-50, 60.
65, 70, 75 and 85 cars.
Service Ir
1. Transmission L u b r i c a n t
It. is important to use the right k i n d and amount
of lubricant in the transmission at all times. T h e
recommended lubricant for all season use in all
37-series Cadillac or LaSalle transmissions is
S. A . E . 90 gear lubricant or S. A . E . 90 m i l d E . P .
lubricant. T h i s grade is preferable to the S. A . E .
160 formerly recommended for summer use,
although S . A . E . 160 can be used the year around
in w a r m climates.
Do Not Use Hypoid Lubricants in the Trans-
mission.
T h e transmission lubricant level must be
inspected every 3,000 miles and lubricant added
as required. . T h e transmission case must be
drained, flushed, and refilled w i t h fresh lubricant
every 6,000 miles.
T h e capacities of 37-series transmissions are as
follows:
Series 37-50, 60, 65, 70, 75 and 8 5 - 2 ½ pts.
Series 37-90 • — 4 ½ pts.
T h e transmission filler plug is on the right hand
side on 37-series V - 8 cars, and on the left hand
side on V-12 and V-16 cars.