procedures a r e d e s i g n e d t o d e t e r m i n e p r o p e r
beyond the scope of this training course. However,
functioning and to assist in isolating and diagnosing
there should be a manufacturer's repair manual
transmission troubles.
ava i l a b l e i n t h e w o r k c e n t e r f o r t h e s p e c i fi c
transmissions for which you have maintenance
F i g u r e 2 - 7 8 s h ow s a t y p i c a l a u t o m a t i c
responsibility. These service and repair manuals
transmission, showing the range or gearing section,
should be followed very closely in performing all
operating units, hydraulic control unit (valve body),
t r a n s m i s s i o n m a i n t e n a n c e a n d r e p a i r. T h e
torque converter, pumps, governor, and transmission
maintenance discussed in the following paragraphs is
case. Optional devices such as lockup clutches,
general in nature and presented to give you a better
high-low splitters, and retarder units are not shown.
understanding of overall transmission maintenance.
You should be familiar with several terms used by
the manufacturers in describing maintenance
Adjustments
procedures for various transmissions. The term
In maintaining the automatic transmission,
apply-passage means a passage through which oil
adjustments are necessary for satisfactory
pressure is applied to an operating unit. Air-check
performance. Adjustments are required after the repair
simply means substituting air pressure for oil pressure
of a transmission and periodically while in service.
and applying it to the apply-passage for checking an
The manufacturer usually specifies the time interval
operating unit. Another term is gauging-hole, which
between most adjustments, and these
refers to holes provided in adjacent parts to hold them
r e c o m m e n d a t i o n s s h o u l d b e f o l l ow e d . T h e
in alignment or in a certain position by a gauge pin or
adjustments discussed in the following paragraphs are
rod. While the parts are held by the gauge pin, certain
the ones most commonly found on automatic
adjustments can be made.
transmissions.
A detailed step-by-step discussion of the possible
Control linkage adjustment is the adjustment of the
repairs that can be performed or how they are
selector linkage to the manual control valve. The
performed for the many automatic transmissions is
INPUT SHAFT
REAR OIL PUMP
REAR BAND
FRONT CLUTCH ASSEMBLY
TRANSMISSION CASE
FRONT BAND
GOVERNOR
ASSEMBLY
OUTPUT SHAFT
OUTPUT SHAFT DRIVE
PLANET PINION CARRIER ASSEMBLY
OIL STRAINER
REAR CLUTCH ASSEMBLY
FRONT OIL PUMP
HYDRAULIC CONTROL UNIT
INTERMEDIATE SHAFT
ASf02078
TORQUE CONVERTER
Figure 2-78.--Typical automatic transmission.
2-63
