Page 32 - Hydra-matic 6 Speed RWD Technician's Guide (October 2005)

APPLY COMPONENTS - LOW and REVERSE CLUTCH

CENTER
SUPPORT
ASSEMBLY
(459) If the low and reverse clutch apply fluid does not fully exhaust,
the low and reverse clutch could partially apply or drag.

LOW AND LOW AND LOW AND LOW AND LOW AND LOW AND
REVERSE REVERSE REVERSE REVERSE REVERSE REVERSE
AIR
LOW AND REVERSE CLUTCH: CLUTCH CLUTCH BLEED CLUTCH CLUTCH CLUTCH
PLATE
PLATE
WAVED
PISTON
SPRING
The low and reverse clutch assembly is located in the center (469) ASSEMBLY (Orifice Cup PLATE (464) ASSEMBLY
support assembly (459). The center support is splined to the (470) Plug) (465) (463)
transmission case, and secured by a large retaining ring (66).
The external teeth on the low and reverse clutch plates (464)
are splined to the center support assembly while the internal
teeth on the low and reverse clutch plate assemblies (463)
are splined to the low clutch sprag assembly (467). The low
and reverse clutch is applied only when the transmission is
in 1st or reverse gears. LOW
CLUTCH
LOW AND REVERSE CLUTCH APPLY: SPRAG
To apply the low and reverse clutch, low and reverse clutch ASSEMBLY
fluid is fed through the transmission case into the center (467)
support assembly (459). A feed hole in the center support
allows fluid to enter behind the low and reverse clutch
piston assembly (470). Low and reverse clutch fluid pressure
moves the piston to compress the low and reverse clutch
spring (469). As fluid pressure increases, the low and reverse LOW
clutch (waved) plate (465) compresses the clutch plates CLUTCH
together until they are held against the backing plate (462). SPRAG
SEAL
When fully applied, the low and reverse clutch (waved) (468)
plate (465), clutch plates (464) and clutch plate assemblies
(463) are locked together, thereby holding the low clutch
sprag assembly outer race. The output carrier assembly
(68) is splined to the low clutch sprag assembly outer race.
Therefore, when the low and reverse clutch is applied, the LOW AND
output carrier will be held stationary. REVERSE
CLUTCH
LOW AND REVERSE CLUTCH RELEASE: SPRING
RETAINING
To release the low and reverse clutch, low and reverse RING
clutch fluid exhausts through the center support assembly (466)
and into the transmission case, allowing pressure at the low
and reverse clutch piston assembly (470) to decrease. In the
absence of fluid pressure, spring force from the low and
reverse clutch spring (469) moves the piston (470) away LOW AND LOW AND
from the clutch pack. This disengages the low and reverse REVERSE REVERSE REVERSE REVERSE
CLUTCH
CLUTCH
clutch plates (464) and clutch plate assemblies (463) from FLUID LOW BACKING BACKING
the backing plate (462), thereby allowing the low clutch FLUID PLATE PLATE
sprag assembly outer race and the output carrier (490) to (462) RETAINING
rotate freely. RING
(461)

470 469 468 467 466 465 464 463 462 461

Figure 23 23