TRUCK SERVICE MANUAL
TRANSMISSION
HT 700D SERIES TRANSMISSIONS
Para 2 -13/2-14
b. Description. The first clutch contain thirteen
clutch plates and a piston. Six are internal-splined clutch
(4) Thirteen clutch plates are required for the
plates and seven are external-tanged clutch plates. The
second clutch. Six internal-splined plates are attached to
external-tanged plates are held stationary by the
the splined area on the outside diameter of the front
transmission housing, while the internal-splined plates
carrier assembly, and are free to rotate. The seven
are free to rotate. The piston for each model is
external-tanged clutch plates a re anchored to the
positioned in its respective bore and retained there by
transmission housing and cannot rotate.
return springs and a spring retainer.
d. Operation (B, foldout 14)
(5) The center support assembly is housed in
the transmission and located by an anchor bolt. This
insures accurate oil passage hole alignment from the
valve body to the second and third piston cavities.
(1) WHEN THE FIRST CLUTCH IS RELEASED
INTERNAL-SPLINED PLATES 2 ARE FREE TO
c. Operation of Third Clutch
ROTATE. SINCE REAR PLANETARY RING GEAR 4
(A, foldout 12)
IS SPLINED TO THE INTERNAL PLATES, IT WILL
ALSO ROTATE FREELY.
(1) When hydraulic pressure is directed
through the oil passages in the center support to the
(2) When hydraulic pressure is directed to the
back side of clutch piston 10, clutch plates 3 and 4 are
back side of piston 6 (A, foldout 15), the piston
compressed together. This locks the fourth clutch
compresses clutch plates 1 (B, foldout 14) and 2
housing to the transmission housing, which prevents the
together. This locks the rotating internal plates to the
fourth clutch housing and attached components from
stationary external plates preventing ring gear 4 from
rotation.
rotating.
clutch in conjunction with third clutch, a reaction within
the planetary gearing will produce a forward rotation to
(3) With the application of forward clutch in
the output shaft.
conjunction with first clutch (refer to a(2), above), a
reaction within the planetary gearing will produce a
d. Operation of Second Clutch
forward rotation at the output shaft.
(A, foldout 12)
2-15. LOW CLUTCH (A, foldout 15)
(1) When hydraulic pressure is directed
through the oil passages in the center support to the
a. Function
front side of clutch piston 21, clutch plates 26 and 27 are
compressed together. This locks the front planetary
(1) Only the five-speed transmissions include
carrier to the transmission housing, which prevents the
the low clutch. Refer to FOLDOUT 2, ITEM 23, FOR ITS
carrier from rotating.
LOCATION
(2) With the application of the forward clutch
(2) The low clutch has a dual function. When
in conjunction with the second clutch, a reaction within
engaged with the forward clutch, it produces first gear.
the planetary gearing will produce a forward rotation to
When engaged with the fourth clutch, it produces
the output shaft.
reverse gear.
2-14. FIRST CLUTCH (B, foldout 14)
b. DESCRIPTION. THE LOW CLUTCH :ONTAIN
THIRTEEN
CLUTCH
PLATES
AND
A
a. Function
(2) The first clutch has a single function.
Engaged with the forward clutch, it produces second
gear.
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